regsub - Perform substitutions based on regular expression pattern matching
regsub ?switches? exp string subSpec varName
This command matches the regular expression exp against
string,
and it copies string to the variable whose name is
given by varName.
If there is a match, then while copying string to varName
the portion of string that
matched exp is replaced with subSpec.
If subSpec contains a ``&'' or ``\0'', then it is replaced
in the substitution with the portion of string that
matched exp.
If subSpec contains a ``\n'', where n is a digit
between 1 and 9, then it is replaced in the substitution with
the portion of string that matched the n-th
parenthesized subexpression of exp.
Additional backslashes may be used in subSpec to prevent special
interpretation of ``&'' or ``\0'' or ``\n'' or
backslash.
The use of backslashes in subSpec tends to interact badly
with the Tcl parser's use of backslashes, so it's generally
safest to enclose subSpec in braces if it includes
backslashes.
If the initial arguments to regexp start with - then
they are treated as switches. The following switches are
currently supported:
- -all
-
All ranges in string that match exp are found and
substitution is performed for each of these ranges.
Without this switch only the first
matching range is found and substituted.
If -all is specified, then ``&'' and ``\n''
sequences are handled for each substitution using the information
from the corresponding match.
- -nocase
-
Upper-case characters in string will be converted to lower-case
before matching against exp; however, substitutions specified
by subSpec use the original unconverted form of string.
- --
-
Marks the end of switches. The argument following this one will
be treated as exp even if it starts with a -.
The command returns a count of the number of matching ranges that
were found and replaced.
See the manual entry for regexp for details on the interpretation
of regular expressions.
match, pattern, regular expression, substitute
Copyright © 1993 The Regents of the University of California.
Copyright © 1994-1996 Sun Microsystems, Inc.
Copyright © 1995, 1996 Roger E. Critchlow Jr.