regexp(n) Tcl Built-In Commands regexp(n)______________________________________________________________________________NAMEregexp - Match a regular expression against a string
SYNOPSISregexp ?switches? exp string ?matchVar? ?subMatchVar subMatchVar ...?
_________________________________________________________________DESCRIPTION
Determines whether the regular expression exp matches part or all of
string and returns 1 if it does, 0 if it doesn't. (Regular expression
matching is described in the re_syntax reference page.)
If additional arguments are specified after string then they are
treated as the names of variables in which to return information about
which part(s) of string matched exp. MatchVar will be set to the range
of string that matched all of exp. The first subMatchVar will contain
the characters in string that matched the leftmost parenthesized subex‐
pression within exp, the next subMatchVar will contain the characters
that matched the next parenthesized subexpression to the right in exp,
and so on.
If the initial arguments to regexp start with - then they are treated
as switches. The following switches are currently supported:
-nocase Causes upper-case characters in string to be treated as
lower case during the matching process.
-indices Changes what is stored in the subMatchVars. Instead of
storing the matching characters from string, each vari‐
able will contain a list of two decimal strings giving
the indices in string of the first and last characters
in the matching range of characters. │
-expanded │
Enables use of the expanded regular expression syntax │
where whitespace and comments are ignored. This is the │
same as specifying the (?x) embedded option (see META‐ │
SYNTAX, below). │
-line │
Enables newline-sensitive matching. By default, newline │
is a completely ordinary character with no special mean‐ │
ing. With this flag, `[^' bracket expressions and `.' │
never match newline, `^' matches an empty string after │
any newline in addition to its normal function, and `$' │
matches an empty string before any newline in addition │
to its normal function. This flag is equivalent to │
specifying both -linestop and -lineanchor, or the (?n) │
embedded option (see METASYNTAX, below). │
-linestop │
Changes the behavior of `[^' bracket expressions and `.' │
so that they stop at newlines. This is the same as │
specifying the (?p) embedded option (see METASYNTAX, │
below). │
-lineanchor │
Changes the behavior of `^' and `$' (the ``anchors'') so │
they match the beginning and end of a line respectively. │
This is the same as specifying the (?w) embedded option │
(see METASYNTAX, below). │
-about │
Instead of attempting to match the regular expression, │
returns a list containing information about the regular │
expression. The first element of the list is a subex‐ │
pression count. The second element is a list of prop‐ │
erty names that describe various attributes of the regu‐ │
lar expression. This switch is primarily intended for │
debugging purposes.
-- Marks the end of switches. The argument following this
one will be treated as exp even if it starts with a -.
If there are more subMatchVar's than parenthesized subexpressions
within exp, or if a particular subexpression in exp doesn't match the
string (e.g. because it was in a portion of the expression that wasn't
matched), then the corresponding subMatchVar will be set to ``-1 -1''
if -indices has been specified or to an empty string otherwise.
SEE ALSOre_syntax(n)KEYWORDS
match, regular expression, string
Tcl 8.1 regexp(n)
