REGEXP-ASSEMBLE(1p) User Contributed Perl Documentation REGEXP-ASSEMBLE(1p)
NAME
regexp-assemble - Assemble a list of regular expressions from a file
SYNOPSIS
regexp-assemble -abcdfinprsStTuUvw file [...]
DESCRIPTION
Assemble a list of regular expression either from standard input or a
file, using the Regexp::Assemble module.
OPTIONS
-a look Ahead. Insert "(?=...)" zero-width lookahead assertions in the
pattern, where necessary.
-b Blank. Ignore blank lines.
-c Comment. Basic comment filtering. Strip off perl/shell comments
("\s*#.*$/").
-d Debug. Turns on debugging output. See Regexp::Assemble for suitable
values.
-i Indent. Print the regular expression using and indent of n to
display nesting. A.k.a pretty-printing. Implies -p.
-n No newline. Do not print a newline after the pattern. Useful when
interpolating the output into a templating system or similar.
-p Print. Print the pattern. This is the default, however, it is
required when the -t switch is enabled (because if you want to test
patterns ordinarily you don't care what the the assembled pattern
looks like).
-r Reduce. The default behaviour is to reduce the assembled pattern.
Enabling this switch causes the reduction algorithm to be switched
off. This can help you determine how much reduction is performed.
regexp-assemble pattern.file | wc
# versus
regexp-assemble -r pattern.file | wc
-s Statistics. Print some statistics about the assembled pattern. The
output is sent to STDERR (in order to allow the generated pattern
to be redirected elsewhere).
-S Statistics only. Like -s, except that the pattern itself is not
output. Useful with -d 8 to see the time taken.
-t Test. Test the assembled expression against the contents of a file.
Each line is read from the file and is matched against the pattern.
Lines that fail to match are printed. In other words, no output is
good output. In this mode of operation, error status is 1 in the
case of a failure, 0 if all lines matched.
-T Time. Print statistics on the time taken to reduce and assemble the
pattern. (This is merely a lazy person's synonym for "-d 8").
-u Unique. Carp if duplicate patterns are found.
-U Unroll. Transform "a+" et al into "aa*" (which may allow additional
reductions).
-v Version. Print the version of the regexp-assemble script.
-w Word/Whole. When testing the contents of a file with "-t", bracket
the expression with "^" and "$" in order to match the whole word or
line from the file.
DIAGNOSTICS
Will print out a summary of the problem if an added pattern causes the
assembly to fail.
SEE ALSO
Regexp::Assemble
AUTHOR
Copyright (C) 2004-2008 David Landgren. All rights reserved.
LICENSE
This script is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
perl v5.36.0 2022-12-04 REGEXP-ASSEMBLE(1p)
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