mirror of https://github.com/python/cpython.git
Logical markup.
Several uses of "\^" could be simplified; this fixes part of the info generation process.
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@ -8,14 +8,14 @@ those found in Perl. It's 8-bit clean: both patterns and strings may
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contain null bytes and characters whose high bit is set. It is always
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available.
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Regular expressions use the backslash character (\code{\e}) to
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Regular expressions use the backslash character (\samp{\e}) to
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indicate special forms or to allow special characters to be used
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without invoking their special meaning. This collides with Python's
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usage of the same character for the same purpose in string literals;
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for example, to match a literal backslash, one might have to write
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\code{\e\e\e\e} as the pattern string, because the regular expression
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must be \code{\e\e}, and each backslash must be expressed as
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\code{\e\e} inside a regular Python string literal.
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\samp{\e\e\e\e} as the pattern string, because the regular expression
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must be \samp{\e\e}, and each backslash must be expressed as
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\samp{\e\e} inside a regular Python string literal.
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The solution is to use Python's raw string notation for regular
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expression patterns; backslashes are not handled in any special way in
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@ -45,14 +45,14 @@ A brief explanation of the format of regular expressions follows.
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%For further information and a gentler presentation, consult XXX somewhere.
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Regular expressions can contain both special and ordinary characters.
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Most ordinary characters, like '\code{A}', '\code{a}', or '\code{0}',
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Most ordinary characters, like \samp{A}, \samp{a}, or \samp{0},
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are the simplest regular expressions; they simply match themselves.
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You can concatenate ordinary characters, so '\code{last}' matches the
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You can concatenate ordinary characters, so \samp{last} matches the
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characters 'last'. (In the rest of this section, we'll write RE's in
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\code{this special font}, usually without quotes, and strings to be
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matched 'in single quotes'.)
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Some characters, like \code{|} or \code{(}, are special. Special
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Some characters, like \samp{|} or \samp{(}, are special. Special
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characters either stand for classes of ordinary characters, or affect
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how the regular expressions around them are interpreted.
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@ -62,12 +62,14 @@ The special characters are:
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\newcommand{\MyLabelWidth}{0.65in}
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\begin{list}{}{\leftmargin \MyLeftMargin \labelwidth \MyLabelWidth}
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\item[\code{.}] (Dot.) In the default mode, this matches any
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character except a newline. If the \code{DOTALL} flag has been
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character except a newline. If the \constant{DOTALL} flag has been
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specified, this matches any character including a newline.
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%
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\item[\code{\^}] (Caret.) Matches the start of the string, and in
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\code{MULTILINE} mode also immediately after each newline.
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\constant{MULTILINE} mode also immediately after each newline.
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%
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\item[\code{\$}] Matches the end of the string, and in
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\code{MULTILINE} mode also matches before a newline.
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\constant{MULTILINE} mode also matches before a newline.
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\code{foo} matches both 'foo' and 'foobar', while the regular
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expression \code{foo\$} matches only 'foo'.
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%
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@ -128,16 +130,16 @@ will match any of the characters 'a', 'k', 'm', or '\$'; \code{[a-z]}
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will match any lowercase letter and \code{[a-zA-Z0-9]} matches any
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letter or digit. Character classes such as \code{\e w} or \code {\e
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S} (defined below) are also acceptable inside a range. If you want to
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include a \code{]} or a \code{-} inside a set, precede it with a
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include a \samp{]} or a \samp{-} inside a set, precede it with a
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backslash.
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Characters \emph{not} within a range can be matched by including a
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\code{\^} as the first character of the set; \code{\^} elsewhere will
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simply match the '\code{\^}' character.
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simply match the \samp{\^} character.
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%
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\item[\code{|}]\code{A|B}, where A and B can be arbitrary REs,
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creates a regular expression that will match either A or B. This can
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be used inside groups (see below) as well. To match a literal '\code{|}',
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be used inside groups (see below) as well. To match a literal \samp{|},
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use \code{\e|}, or enclose it inside a character class, like \code{[|]}.
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%
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\item[\code{(...)}] Matches whatever regular expression is inside the
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@ -153,13 +155,13 @@ class: \code{[(] [)]}.
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determines what the meaning and further syntax of the construct is.
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Following are the currently supported extensions.
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%
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\item[\code{(?iLmsx)}] (One or more letters from the set '\code{i}',
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'\code{L}', '\code{m}', '\code{s}', '\code{x}'.) The group matches
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\item[\code{(?iLmsx)}] (One or more letters from the set \samp{i},
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\samp{L}, \samp{m}, \samp{s}, \samp{x}.) The group matches
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the empty string; the letters set the corresponding flags
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(\code{re.I}, \code{re.L}, \code{re.M}, \code{re.S}, \code{re.X}) for
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the entire regular expression. This is useful if you wish include the
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flags as part of the regular expression, instead of passing a
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\var{flag} argument to the \code{compile()} function.
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(\constant{re.I}, \constant{re.L}, \constant{re.M}, \constant{re.S},
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\constant{re.X}) for the entire regular expression. This is useful if
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you wish include the flags as part of the regular expression, instead
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of passing a \var{flag} argument to the \function{compile()} function.
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%
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\item[\code{(?:...)}] A non-grouping version of regular parentheses.
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Matches whatever's inside the parentheses, but the text matched by the
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@ -197,10 +199,10 @@ followed by 'Asimov'.
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\end{list}
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The special sequences consist of '\code{\e}' and a character from the
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The special sequences consist of \samp{\e} and a character from the
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list below. If the ordinary character is not on the list, then the
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resulting RE will match the second character. For example,
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\code{\e\$} matches the character '\$'.
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\code{\e\$} matches the character \samp{\$}.
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\begin{list}{}{\leftmargin \MyLeftMargin \labelwidth \MyLabelWidth}
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@ -229,7 +231,7 @@ Python's string literals.
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equivalent to the set \code{[0-9]}.
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%
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\item[\code{\e D}]Matches any non-digit character; this is
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equivalent to the set \code{[{\^}0-9]}.
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equivalent to the set \code{[\^0-9]}.
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%
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\item[\code{\e s}]Matches any whitespace character; this is
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equivalent to the set \code{[ \e t\e n\e r\e f\e v]}.
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@ -237,15 +239,15 @@ equivalent to the set \code{[ \e t\e n\e r\e f\e v]}.
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\item[\code{\e S}]Matches any non-whitespace character; this is
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equivalent to the set \code{[\^\ \e t\e n\e r\e f\e v]}.
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%
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\item[\code{\e w}]When the \code{LOCALE} flag is not specified,
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\item[\code{\e w}]When the \constant{LOCALE} flag is not specified,
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matches any alphanumeric character; this is equivalent to the set
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\code{[a-zA-Z0-9_]}. With \code{LOCALE}, it will match the set
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\code{[a-zA-Z0-9_]}. With \constant{LOCALE}, it will match the set
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\code{[0-9_]} plus whatever characters are defined as letters for the
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current locale.
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%
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\item[\code{\e W}]When the \code{LOCALE} flag is not specified,
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\item[\code{\e W}]When the \constant{LOCALE} flag is not specified,
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matches any non-alphanumeric character; this is equivalent to the set
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\code{[{\^}a-zA-Z0-9_]}. With \code{LOCALE}, it will match any
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\code{[\^a-zA-Z0-9_]}. With \constant{LOCALE}, it will match any
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character not in the set \code{[0-9_]}, and not defined as a letter
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for the current locale.
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@ -265,8 +267,8 @@ The module defines the following functions and constants, and an exception:
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\begin{funcdesc}{compile}{pattern\optional{\, flags}}
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Compile a regular expression pattern into a regular expression
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object, which can be used for matching using its \code{match()} and
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\code{search()} methods, described below.
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object, which can be used for matching using its \function{match()} and
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\function{search()} methods, described below.
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The expression's behaviour can be modified by specifying a
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\var{flags} value. Values can be any of the following variables,
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@ -277,17 +279,17 @@ The module defines the following functions and constants, and an exception:
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% The use of \quad in the item labels is ugly but adds enough space
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% to the label that it doesn't get visually run-in with the text.
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\item[\code{I} or \code{IGNORECASE} or \code{(?i)}\quad]
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\item[\constant{I} or \constant{IGNORECASE} or \code{(?i)}\quad]
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Perform case-insensitive matching; expressions like \code{[A-Z]} will match
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lowercase letters, too. This is not affected by the current locale.
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\item[\code{L} or \code{LOCALE} or \code{(?L)}\quad]
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\item[\constant{L} or \constant{LOCALE} or \constant{(?L)}\quad]
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Make \code{\e w}, \code{\e W}, \code{\e b},
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\code{\e B}, dependent on the current locale.
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\item[\code{M} or \code{MULTILINE} or \code{(?m)}\quad]
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\item[\constant{M} or \constant{MULTILINE} or \constant{(?m)}\quad]
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When specified, the pattern character \code{\^} matches at the
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beginning of the string and at the beginning of each line
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@ -298,13 +300,13 @@ By default, \code{\^} matches only at the beginning of the string, and
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\code{\$} only at the end of the string and immediately before the
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newline (if any) at the end of the string.
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\item[\code{S} or \code{DOTALL} or \code{(?s)}\quad]
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\item[\constant{S} or \constant{DOTALL} or \constant{(?s)}\quad]
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Make the \code{.} special character any character at all, including a
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newline; without this flag, \code{.} will match anything \emph{except}
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a newline.
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\item[\code{X} or \code{VERBOSE} or \code{(?x)}\quad]
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\item[\constant{X} or \constant{VERBOSE} or \constant{(?x)}\quad]
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Ignore whitespace within the pattern
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except when in a character class or preceded by an unescaped
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result = re.match(pat, str)
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\end{verbatim}
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but the version using \code{compile()} is more efficient when the
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but the version using \function{compile()} is more efficient when the
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expression will be used several times in a single program.
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%(The compiled version of the last pattern passed to \code{regex.match()} or
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%\code{regex.search()} is cached, so programs that use only a single
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%regular expression at a time needn't worry about compiling regular
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%expressions.)
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%(The compiled version of the last pattern passed to
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%\function{regex.match()} or \function{regex.search()} is cached, so
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%programs that use only a single regular expression at a time needn't
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%worry about compiling regular expressions.)
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\end{funcdesc}
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\begin{funcdesc}{escape}{string}
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@ -344,7 +346,7 @@ expression will be used several times in a single program.
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\begin{funcdesc}{match}{pattern\, string\optional{\, flags}}
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If zero or more characters at the beginning of \var{string} match
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the regular expression \var{pattern}, return a corresponding
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\code{MatchObject} instance. Return \code{None} if the string does not
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\class{MatchObject} instance. Return \code{None} if the string does not
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match the pattern; note that this is different from a zero-length
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match.
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\end{funcdesc}
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@ -352,7 +354,7 @@ expression will be used several times in a single program.
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\begin{funcdesc}{search}{pattern\, string\optional{\, flags}}
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Scan through \var{string} looking for a location where the regular
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expression \var{pattern} produces a match, and return a
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corresponding \code{MatchObject} instance.
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corresponding \class{MatchObject} instance.
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Return \code{None} if no
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position in the string matches the pattern; note that this is
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different from finding a zero-length match at some point in the string.
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@ -378,7 +380,7 @@ expression will be used several times in a single program.
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\end{verbatim}
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%
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This function combines and extends the functionality of
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the old \code{regsub.split()} and \code{regsub.splitx()}.
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the old \function{regsub.split()} and \function{regsub.splitx()}.
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\end{funcdesc}
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\begin{funcdesc}{sub}{pattern\, repl\, string\optional{, count=0}}
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@ -416,7 +418,7 @@ previous match, so \code{sub('x*', '-', 'abc')} returns '-a-b-c-'.
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\end{funcdesc}
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\begin{funcdesc}{subn}{pattern\, repl\, string\optional{, count=0}}
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Perform the same operation as \code{sub()}, but return a tuple
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Perform the same operation as \function{sub()}, but return a tuple
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\code{(\var{new_string}, \var{number_of_subs_made})}.
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\end{funcdesc}
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@ -435,13 +437,13 @@ attributes:
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\begin{funcdesc}{match}{string\optional{\, pos}\optional{\, endpos}}
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If zero or more characters at the beginning of \var{string} match
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this regular expression, return a corresponding
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\code{MatchObject} instance. Return \code{None} if the string does not
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\class{MatchObject} instance. Return \code{None} if the string does not
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match the pattern; note that this is different from a zero-length
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match.
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The optional second parameter \var{pos} gives an index in the string
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where the search is to start; it defaults to \code{0}. The
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\code{'\^'} pattern character will match at the index where the
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\samp{\^} pattern character will match at the index where the
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search is to start.
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The optional parameter \var{endpos} limits how far the string will
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@ -457,19 +459,19 @@ attributes:
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different from finding a zero-length match at some point in the string.
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The optional \var{pos} and \var{endpos} parameters have the same
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meaning as for the \code{match()} method.
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meaning as for the \method{match()} method.
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\end{funcdesc}
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\begin{funcdesc}{split}{string\, \optional{, maxsplit=0}}
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Identical to the \code{split()} function, using the compiled pattern.
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Identical to the \function{split()} function, using the compiled pattern.
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\end{funcdesc}
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\begin{funcdesc}{sub}{repl\, string\optional{, count=0}}
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Identical to the \code{sub()} function, using the compiled pattern.
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Identical to the \function{sub()} function, using the compiled pattern.
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\end{funcdesc}
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\begin{funcdesc}{subn}{repl\, string\optional{, count=0}}
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Identical to the \code{subn()} function, using the compiled pattern.
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Identical to the \function{subn()} function, using the compiled pattern.
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\end{funcdesc}
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\setindexsubitem{(regex attribute)}
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\subsection{Match Objects}
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\code{MatchObject} instances support the following methods and attributes:
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\class{MatchObject} instances support the following methods and attributes:
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\begin{funcdesc}{group}{\optional{group1, group2, ...}}
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Returns one or more subgroups of the match. If there is a single
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re.search('b(c?)', 'cba')}, \code{\var{m}.start(0)} is 1,
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\code{\var{m}.end(0)} is 2, \code{\var{m}.start(1)} and
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\code{\var{m}.end(1)} are both 2, and \code{\var{m}.start(2)} raises
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an \code{IndexError} exception.
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an \exception{IndexError} exception.
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\end{funcdesc}
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\begin{funcdesc}{span}{\optional{group}}
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For \code{MatchObject} \var{m}, return the 2-tuple
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For \class{MatchObject} \var{m}, return the 2-tuple
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\code{(\var{m}.start(\var{group}), \var{m}.end(\var{group}))}.
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Note that if \var{group} did not contribute to the match, this is
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\code{(None, None)}. Again, \var{group} defaults to zero.
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@ -564,28 +566,28 @@ Note that if \var{group} did not contribute to the match, this is
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\begin{datadesc}{pos}
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The value of \var{pos} which was passed to the
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\code{search()} or \code{match()} function. This is the index into
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\function{search()} or \function{match()} function. This is the index into
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the string at which the regex engine started looking for a match.
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\end{datadesc}
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\begin{datadesc}{endpos}
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The value of \var{endpos} which was passed to the
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\code{search()} or \code{match()} function. This is the index into
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\function{search()} or \function{match()} function. This is the index into
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the string beyond which the regex engine will not go.
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\end{datadesc}
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\begin{datadesc}{re}
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The regular expression object whose \code{match()} or \code{search()} method
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produced this \code{MatchObject} instance.
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The regular expression object whose \method{match()} or
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\method{search()} method produced this \class{MatchObject} instance.
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\end{datadesc}
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\begin{datadesc}{string}
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The string passed to \code{match()} or \code{search()}.
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The string passed to \function{match()} or \function{search()}.
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\end{datadesc}
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\begin{seealso}
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\seetext{Jeffrey Friedl, \emph{Mastering Regular Expressions},
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O'Reilly. The Python material in this book dates from before the
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\code{re} module, but it covers writing good regular expression
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\module{re} module, but it covers writing good regular expression
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patterns in great detail.}
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\end{seealso}
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|
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116
Doc/libre.tex
116
Doc/libre.tex
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@ -8,14 +8,14 @@ those found in Perl. It's 8-bit clean: both patterns and strings may
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contain null bytes and characters whose high bit is set. It is always
|
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available.
|
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|
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Regular expressions use the backslash character (\code{\e}) to
|
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Regular expressions use the backslash character (\samp{\e}) to
|
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indicate special forms or to allow special characters to be used
|
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without invoking their special meaning. This collides with Python's
|
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usage of the same character for the same purpose in string literals;
|
||||
for example, to match a literal backslash, one might have to write
|
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\code{\e\e\e\e} as the pattern string, because the regular expression
|
||||
must be \code{\e\e}, and each backslash must be expressed as
|
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\code{\e\e} inside a regular Python string literal.
|
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\samp{\e\e\e\e} as the pattern string, because the regular expression
|
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must be \samp{\e\e}, and each backslash must be expressed as
|
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\samp{\e\e} inside a regular Python string literal.
|
||||
|
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The solution is to use Python's raw string notation for regular
|
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expression patterns; backslashes are not handled in any special way in
|
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|
@ -45,14 +45,14 @@ A brief explanation of the format of regular expressions follows.
|
|||
%For further information and a gentler presentation, consult XXX somewhere.
|
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|
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Regular expressions can contain both special and ordinary characters.
|
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Most ordinary characters, like '\code{A}', '\code{a}', or '\code{0}',
|
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Most ordinary characters, like \samp{A}, \samp{a}, or \samp{0},
|
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are the simplest regular expressions; they simply match themselves.
|
||||
You can concatenate ordinary characters, so '\code{last}' matches the
|
||||
You can concatenate ordinary characters, so \samp{last} matches the
|
||||
characters 'last'. (In the rest of this section, we'll write RE's in
|
||||
\code{this special font}, usually without quotes, and strings to be
|
||||
matched 'in single quotes'.)
|
||||
|
||||
Some characters, like \code{|} or \code{(}, are special. Special
|
||||
Some characters, like \samp{|} or \samp{(}, are special. Special
|
||||
characters either stand for classes of ordinary characters, or affect
|
||||
how the regular expressions around them are interpreted.
|
||||
|
||||
|
@ -62,12 +62,14 @@ The special characters are:
|
|||
\newcommand{\MyLabelWidth}{0.65in}
|
||||
\begin{list}{}{\leftmargin \MyLeftMargin \labelwidth \MyLabelWidth}
|
||||
\item[\code{.}] (Dot.) In the default mode, this matches any
|
||||
character except a newline. If the \code{DOTALL} flag has been
|
||||
character except a newline. If the \constant{DOTALL} flag has been
|
||||
specified, this matches any character including a newline.
|
||||
%
|
||||
\item[\code{\^}] (Caret.) Matches the start of the string, and in
|
||||
\code{MULTILINE} mode also immediately after each newline.
|
||||
\constant{MULTILINE} mode also immediately after each newline.
|
||||
%
|
||||
\item[\code{\$}] Matches the end of the string, and in
|
||||
\code{MULTILINE} mode also matches before a newline.
|
||||
\constant{MULTILINE} mode also matches before a newline.
|
||||
\code{foo} matches both 'foo' and 'foobar', while the regular
|
||||
expression \code{foo\$} matches only 'foo'.
|
||||
%
|
||||
|
@ -128,16 +130,16 @@ will match any of the characters 'a', 'k', 'm', or '\$'; \code{[a-z]}
|
|||
will match any lowercase letter and \code{[a-zA-Z0-9]} matches any
|
||||
letter or digit. Character classes such as \code{\e w} or \code {\e
|
||||
S} (defined below) are also acceptable inside a range. If you want to
|
||||
include a \code{]} or a \code{-} inside a set, precede it with a
|
||||
include a \samp{]} or a \samp{-} inside a set, precede it with a
|
||||
backslash.
|
||||
|
||||
Characters \emph{not} within a range can be matched by including a
|
||||
\code{\^} as the first character of the set; \code{\^} elsewhere will
|
||||
simply match the '\code{\^}' character.
|
||||
simply match the \samp{\^} character.
|
||||
%
|
||||
\item[\code{|}]\code{A|B}, where A and B can be arbitrary REs,
|
||||
creates a regular expression that will match either A or B. This can
|
||||
be used inside groups (see below) as well. To match a literal '\code{|}',
|
||||
be used inside groups (see below) as well. To match a literal \samp{|},
|
||||
use \code{\e|}, or enclose it inside a character class, like \code{[|]}.
|
||||
%
|
||||
\item[\code{(...)}] Matches whatever regular expression is inside the
|
||||
|
@ -153,13 +155,13 @@ class: \code{[(] [)]}.
|
|||
determines what the meaning and further syntax of the construct is.
|
||||
Following are the currently supported extensions.
|
||||
%
|
||||
\item[\code{(?iLmsx)}] (One or more letters from the set '\code{i}',
|
||||
'\code{L}', '\code{m}', '\code{s}', '\code{x}'.) The group matches
|
||||
\item[\code{(?iLmsx)}] (One or more letters from the set \samp{i},
|
||||
\samp{L}, \samp{m}, \samp{s}, \samp{x}.) The group matches
|
||||
the empty string; the letters set the corresponding flags
|
||||
(\code{re.I}, \code{re.L}, \code{re.M}, \code{re.S}, \code{re.X}) for
|
||||
the entire regular expression. This is useful if you wish include the
|
||||
flags as part of the regular expression, instead of passing a
|
||||
\var{flag} argument to the \code{compile()} function.
|
||||
(\constant{re.I}, \constant{re.L}, \constant{re.M}, \constant{re.S},
|
||||
\constant{re.X}) for the entire regular expression. This is useful if
|
||||
you wish include the flags as part of the regular expression, instead
|
||||
of passing a \var{flag} argument to the \function{compile()} function.
|
||||
%
|
||||
\item[\code{(?:...)}] A non-grouping version of regular parentheses.
|
||||
Matches whatever's inside the parentheses, but the text matched by the
|
||||
|
@ -197,10 +199,10 @@ followed by 'Asimov'.
|
|||
|
||||
\end{list}
|
||||
|
||||
The special sequences consist of '\code{\e}' and a character from the
|
||||
The special sequences consist of \samp{\e} and a character from the
|
||||
list below. If the ordinary character is not on the list, then the
|
||||
resulting RE will match the second character. For example,
|
||||
\code{\e\$} matches the character '\$'.
|
||||
\code{\e\$} matches the character \samp{\$}.
|
||||
|
||||
\begin{list}{}{\leftmargin \MyLeftMargin \labelwidth \MyLabelWidth}
|
||||
|
||||
|
@ -229,7 +231,7 @@ Python's string literals.
|
|||
equivalent to the set \code{[0-9]}.
|
||||
%
|
||||
\item[\code{\e D}]Matches any non-digit character; this is
|
||||
equivalent to the set \code{[{\^}0-9]}.
|
||||
equivalent to the set \code{[\^0-9]}.
|
||||
%
|
||||
\item[\code{\e s}]Matches any whitespace character; this is
|
||||
equivalent to the set \code{[ \e t\e n\e r\e f\e v]}.
|
||||
|
@ -237,15 +239,15 @@ equivalent to the set \code{[ \e t\e n\e r\e f\e v]}.
|
|||
\item[\code{\e S}]Matches any non-whitespace character; this is
|
||||
equivalent to the set \code{[\^\ \e t\e n\e r\e f\e v]}.
|
||||
%
|
||||
\item[\code{\e w}]When the \code{LOCALE} flag is not specified,
|
||||
\item[\code{\e w}]When the \constant{LOCALE} flag is not specified,
|
||||
matches any alphanumeric character; this is equivalent to the set
|
||||
\code{[a-zA-Z0-9_]}. With \code{LOCALE}, it will match the set
|
||||
\code{[a-zA-Z0-9_]}. With \constant{LOCALE}, it will match the set
|
||||
\code{[0-9_]} plus whatever characters are defined as letters for the
|
||||
current locale.
|
||||
%
|
||||
\item[\code{\e W}]When the \code{LOCALE} flag is not specified,
|
||||
\item[\code{\e W}]When the \constant{LOCALE} flag is not specified,
|
||||
matches any non-alphanumeric character; this is equivalent to the set
|
||||
\code{[{\^}a-zA-Z0-9_]}. With \code{LOCALE}, it will match any
|
||||
\code{[\^a-zA-Z0-9_]}. With \constant{LOCALE}, it will match any
|
||||
character not in the set \code{[0-9_]}, and not defined as a letter
|
||||
for the current locale.
|
||||
|
||||
|
@ -265,8 +267,8 @@ The module defines the following functions and constants, and an exception:
|
|||
|
||||
\begin{funcdesc}{compile}{pattern\optional{\, flags}}
|
||||
Compile a regular expression pattern into a regular expression
|
||||
object, which can be used for matching using its \code{match()} and
|
||||
\code{search()} methods, described below.
|
||||
object, which can be used for matching using its \function{match()} and
|
||||
\function{search()} methods, described below.
|
||||
|
||||
The expression's behaviour can be modified by specifying a
|
||||
\var{flags} value. Values can be any of the following variables,
|
||||
|
@ -277,17 +279,17 @@ The module defines the following functions and constants, and an exception:
|
|||
% The use of \quad in the item labels is ugly but adds enough space
|
||||
% to the label that it doesn't get visually run-in with the text.
|
||||
|
||||
\item[\code{I} or \code{IGNORECASE} or \code{(?i)}\quad]
|
||||
\item[\constant{I} or \constant{IGNORECASE} or \code{(?i)}\quad]
|
||||
|
||||
Perform case-insensitive matching; expressions like \code{[A-Z]} will match
|
||||
lowercase letters, too. This is not affected by the current locale.
|
||||
|
||||
\item[\code{L} or \code{LOCALE} or \code{(?L)}\quad]
|
||||
\item[\constant{L} or \constant{LOCALE} or \constant{(?L)}\quad]
|
||||
|
||||
Make \code{\e w}, \code{\e W}, \code{\e b},
|
||||
\code{\e B}, dependent on the current locale.
|
||||
|
||||
\item[\code{M} or \code{MULTILINE} or \code{(?m)}\quad]
|
||||
\item[\constant{M} or \constant{MULTILINE} or \constant{(?m)}\quad]
|
||||
|
||||
When specified, the pattern character \code{\^} matches at the
|
||||
beginning of the string and at the beginning of each line
|
||||
|
@ -298,13 +300,13 @@ By default, \code{\^} matches only at the beginning of the string, and
|
|||
\code{\$} only at the end of the string and immediately before the
|
||||
newline (if any) at the end of the string.
|
||||
|
||||
\item[\code{S} or \code{DOTALL} or \code{(?s)}\quad]
|
||||
\item[\constant{S} or \constant{DOTALL} or \constant{(?s)}\quad]
|
||||
|
||||
Make the \code{.} special character any character at all, including a
|
||||
newline; without this flag, \code{.} will match anything \emph{except}
|
||||
a newline.
|
||||
|
||||
\item[\code{X} or \code{VERBOSE} or \code{(?x)}\quad]
|
||||
\item[\constant{X} or \constant{VERBOSE} or \constant{(?x)}\quad]
|
||||
|
||||
Ignore whitespace within the pattern
|
||||
except when in a character class or preceded by an unescaped
|
||||
|
@ -327,12 +329,12 @@ is equivalent to
|
|||
result = re.match(pat, str)
|
||||
\end{verbatim}
|
||||
|
||||
but the version using \code{compile()} is more efficient when the
|
||||
but the version using \function{compile()} is more efficient when the
|
||||
expression will be used several times in a single program.
|
||||
%(The compiled version of the last pattern passed to \code{regex.match()} or
|
||||
%\code{regex.search()} is cached, so programs that use only a single
|
||||
%regular expression at a time needn't worry about compiling regular
|
||||
%expressions.)
|
||||
%(The compiled version of the last pattern passed to
|
||||
%\function{regex.match()} or \function{regex.search()} is cached, so
|
||||
%programs that use only a single regular expression at a time needn't
|
||||
%worry about compiling regular expressions.)
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{escape}{string}
|
||||
|
@ -344,7 +346,7 @@ expression will be used several times in a single program.
|
|||
\begin{funcdesc}{match}{pattern\, string\optional{\, flags}}
|
||||
If zero or more characters at the beginning of \var{string} match
|
||||
the regular expression \var{pattern}, return a corresponding
|
||||
\code{MatchObject} instance. Return \code{None} if the string does not
|
||||
\class{MatchObject} instance. Return \code{None} if the string does not
|
||||
match the pattern; note that this is different from a zero-length
|
||||
match.
|
||||
\end{funcdesc}
|
||||
|
@ -352,7 +354,7 @@ expression will be used several times in a single program.
|
|||
\begin{funcdesc}{search}{pattern\, string\optional{\, flags}}
|
||||
Scan through \var{string} looking for a location where the regular
|
||||
expression \var{pattern} produces a match, and return a
|
||||
corresponding \code{MatchObject} instance.
|
||||
corresponding \class{MatchObject} instance.
|
||||
Return \code{None} if no
|
||||
position in the string matches the pattern; note that this is
|
||||
different from finding a zero-length match at some point in the string.
|
||||
|
@ -378,7 +380,7 @@ expression will be used several times in a single program.
|
|||
\end{verbatim}
|
||||
%
|
||||
This function combines and extends the functionality of
|
||||
the old \code{regsub.split()} and \code{regsub.splitx()}.
|
||||
the old \function{regsub.split()} and \function{regsub.splitx()}.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{sub}{pattern\, repl\, string\optional{, count=0}}
|
||||
|
@ -416,7 +418,7 @@ previous match, so \code{sub('x*', '-', 'abc')} returns '-a-b-c-'.
|
|||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{subn}{pattern\, repl\, string\optional{, count=0}}
|
||||
Perform the same operation as \code{sub()}, but return a tuple
|
||||
Perform the same operation as \function{sub()}, but return a tuple
|
||||
\code{(\var{new_string}, \var{number_of_subs_made})}.
|
||||
\end{funcdesc}
|
||||
|
||||
|
@ -435,13 +437,13 @@ attributes:
|
|||
\begin{funcdesc}{match}{string\optional{\, pos}\optional{\, endpos}}
|
||||
If zero or more characters at the beginning of \var{string} match
|
||||
this regular expression, return a corresponding
|
||||
\code{MatchObject} instance. Return \code{None} if the string does not
|
||||
\class{MatchObject} instance. Return \code{None} if the string does not
|
||||
match the pattern; note that this is different from a zero-length
|
||||
match.
|
||||
|
||||
The optional second parameter \var{pos} gives an index in the string
|
||||
where the search is to start; it defaults to \code{0}. The
|
||||
\code{'\^'} pattern character will match at the index where the
|
||||
\samp{\^} pattern character will match at the index where the
|
||||
search is to start.
|
||||
|
||||
The optional parameter \var{endpos} limits how far the string will
|
||||
|
@ -457,19 +459,19 @@ attributes:
|
|||
different from finding a zero-length match at some point in the string.
|
||||
|
||||
The optional \var{pos} and \var{endpos} parameters have the same
|
||||
meaning as for the \code{match()} method.
|
||||
meaning as for the \method{match()} method.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{split}{string\, \optional{, maxsplit=0}}
|
||||
Identical to the \code{split()} function, using the compiled pattern.
|
||||
Identical to the \function{split()} function, using the compiled pattern.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{sub}{repl\, string\optional{, count=0}}
|
||||
Identical to the \code{sub()} function, using the compiled pattern.
|
||||
Identical to the \function{sub()} function, using the compiled pattern.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{subn}{repl\, string\optional{, count=0}}
|
||||
Identical to the \code{subn()} function, using the compiled pattern.
|
||||
Identical to the \function{subn()} function, using the compiled pattern.
|
||||
\end{funcdesc}
|
||||
|
||||
\setindexsubitem{(regex attribute)}
|
||||
|
@ -491,7 +493,7 @@ The pattern string from which the regex object was compiled.
|
|||
|
||||
\subsection{Match Objects}
|
||||
|
||||
\code{MatchObject} instances support the following methods and attributes:
|
||||
\class{MatchObject} instances support the following methods and attributes:
|
||||
|
||||
\begin{funcdesc}{group}{\optional{group1, group2, ...}}
|
||||
Returns one or more subgroups of the match. If there is a single
|
||||
|
@ -551,12 +553,12 @@ Note that
|
|||
re.search('b(c?)', 'cba')}, \code{\var{m}.start(0)} is 1,
|
||||
\code{\var{m}.end(0)} is 2, \code{\var{m}.start(1)} and
|
||||
\code{\var{m}.end(1)} are both 2, and \code{\var{m}.start(2)} raises
|
||||
an \code{IndexError} exception.
|
||||
an \exception{IndexError} exception.
|
||||
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{span}{\optional{group}}
|
||||
For \code{MatchObject} \var{m}, return the 2-tuple
|
||||
For \class{MatchObject} \var{m}, return the 2-tuple
|
||||
\code{(\var{m}.start(\var{group}), \var{m}.end(\var{group}))}.
|
||||
Note that if \var{group} did not contribute to the match, this is
|
||||
\code{(None, None)}. Again, \var{group} defaults to zero.
|
||||
|
@ -564,28 +566,28 @@ Note that if \var{group} did not contribute to the match, this is
|
|||
|
||||
\begin{datadesc}{pos}
|
||||
The value of \var{pos} which was passed to the
|
||||
\code{search()} or \code{match()} function. This is the index into
|
||||
\function{search()} or \function{match()} function. This is the index into
|
||||
the string at which the regex engine started looking for a match.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{endpos}
|
||||
The value of \var{endpos} which was passed to the
|
||||
\code{search()} or \code{match()} function. This is the index into
|
||||
\function{search()} or \function{match()} function. This is the index into
|
||||
the string beyond which the regex engine will not go.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{re}
|
||||
The regular expression object whose \code{match()} or \code{search()} method
|
||||
produced this \code{MatchObject} instance.
|
||||
The regular expression object whose \method{match()} or
|
||||
\method{search()} method produced this \class{MatchObject} instance.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{string}
|
||||
The string passed to \code{match()} or \code{search()}.
|
||||
The string passed to \function{match()} or \function{search()}.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{seealso}
|
||||
\seetext{Jeffrey Friedl, \emph{Mastering Regular Expressions},
|
||||
O'Reilly. The Python material in this book dates from before the
|
||||
\code{re} module, but it covers writing good regular expression
|
||||
\module{re} module, but it covers writing good regular expression
|
||||
patterns in great detail.}
|
||||
\end{seealso}
|
||||
|
|
Loading…
Reference in New Issue