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Perl one liner to extract a multi-line pattern

I have a template in a file that may / may not span multiple lines:

 abcd25
 ef_gh
 ( fg*_h
 hj_b*
 hj ) {

What I tried:

perl -nle 'print while m / ^ \ s * (\ w +) \ s + (\ w +?) \ s * (([\ w-0-9, * \ s])) \ s {/ gm

I don't know what flags mean here, but all I did was write regexfor the template and paste it into the template space. This works well if the template is on the same line as:

abcd25 ef_gh ( fg*_h hj_b* hj ) {

But it crashes exclusively in the multi-line case!

I started with perl yesterday, but the syntax is too confusing. So, as one of our SO partners suggested, I wrote a regexand pasted it into the code it provided.

I hope the monk perlcan help me in this case. Alternative solutions are welcome.

Input file:

 abcd25
 ef_gh
 ( fg*_h
 hj_b*
 hj ) {

 abcd25
 ef_gh
 fg*_h
 hj_b*
 hj ) {

 jhijdsiokdù ()lmolmlxjk;
 abcd25 ef_gh ( fg*_h hj_b* hj ) {

:

 abcd25
 ef_gh
 ( fg*_h
 hj_b*
 hj ) {
 abcd25 ef_gh ( fg*_h hj_b* hj ) {

, . .

+5
2

. , ?

,

m/^\s*(\w+)\s+(\w+?)\s*\([\w0-9,*\s]+\)\s{/gm

: . () , :

perl -0777 -nle 'print "$1\n" while m/^\s*(\w+\s+\w+?\s*\([\w0-9,*\s]+\)\s{)/gm'

:

:

  • perlrun: zero, n, l, e

  • YAPE::Regex::Explain

    perl -MYAPE::Regex::Explain -e 'print YAPE::Regex::Explain->new(qr/^\s*(\w+\s+\w+?\s*\([\w0-9,*\s]+\)\s{)/)->explain'
The regular expression:

(?-imsx:^\s*(\w+\s+\w+?\s*\([\w0-9,*\s]+\)\s{))

matches as follows:

NODE                     EXPLANATION
----------------------------------------------------------------------
(?-imsx:                 group, but do not capture (case-sensitive)
                         (with ^ and $ matching normally) (with . not
                         matching \n) (matching whitespace and #
                         normally):
----------------------------------------------------------------------
  ^                        the beginning of the string
----------------------------------------------------------------------
  \s*                      whitespace (\n, \r, \t, \f, and " ") (0 or
                           more times (matching the most amount
                           possible))
----------------------------------------------------------------------
  (                        group and capture to \1:
----------------------------------------------------------------------
    \w+                      word characters (a-z, A-Z, 0-9, _) (1 or
                             more times (matching the most amount
                             possible))
----------------------------------------------------------------------
    \s+                      whitespace (\n, \r, \t, \f, and " ") (1
                             or more times (matching the most amount
                             possible))
----------------------------------------------------------------------
    \w+?                     word characters (a-z, A-Z, 0-9, _) (1 or
                             more times (matching the least amount
                             possible))
----------------------------------------------------------------------
    \s*                      whitespace (\n, \r, \t, \f, and " ") (0
                             or more times (matching the most amount
                             possible))
----------------------------------------------------------------------
    \(                       '('
----------------------------------------------------------------------
    [\w0-9,*\s]+             any character of: word characters (a-z,
                             A-Z, 0-9, _), '0' to '9', ',', '*',
                             whitespace (\n, \r, \t, \f, and " ") (1
                             or more times (matching the most amount
                             possible))
----------------------------------------------------------------------
    \)                       ')'
----------------------------------------------------------------------
    \s                       whitespace (\n, \r, \t, \f, and " ")
----------------------------------------------------------------------
    {                        '{'
----------------------------------------------------------------------
  )                        end of \1
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------
+5

Flip-Flop

Perl --, . :

$ perl -ne 'print if /^abcd25/ ... /\bhj \) {/' /tmp/foo
abcd25
ef_gh
( fg*_h
hj_b*
hj ) {

, , , . .

, - , . , , .

- , , . :

#!/usr/bin/perl -nw

# Use flip-flop operator to select matches.
if (/^abcd25/ ... /\bhj \) {/) {
    push @string, $_
};

# Reject multi-line patterns that don't include a particular expression
# between flip-flop delimiters. For example, "( fg" will match, while
# "^fg" won't.
if (/\bhj \) {/) {
    $string = join("", @string);
    undef @string;
    push(@matches, $string) if $string =~ /\( fg/;
};

END {print @matches}

OP :

abcd25
ef_gh
( fg*_h
hj_b*
hj ) {
abcd25 ef_gh ( fg*_h hj_b* hj ) {
+5

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