Re: How do I replace a substring (if exists) with a different substring in a string?

in reply to How do I replace a substring (if exists) with a different substring in a string?

You can use substr, length, and index inside a while loop to do what you want:

  my $string  = '01234567890';
  my $find    = '0';
  my $replace = 'a';  

  my $pos = index($string, $find);

  while($pos > -1) {
    substr($string, $pos, length($find), $replace);
    $pos = index($string, $find, $pos + length($replace));
  }
[download]

IMHO you can't beat the following for readability:

  $string =~ s/\Q$find\E/$replace/g;
[download]

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(dkubb) Re: (3) Answer: How do I replace a substring (if exists) with a different substring in a string? by dkubb (Deacon) on Jul 22, 2001 at 02:00 UTC
Note: I found a bug in my earlier answer, since I can't edit it, I am posting this follow up. If the string to replace has the substring you are trying to find, it can get into an endless loop. Here is an updated ansewer: `my $string = '01234567890'; my $find = '0'; my $replace = 'a'; my $pos = index($string, $find); while($pos > -1) { substr($string, $pos, length($find), $replace); $pos = index($string, $find, $pos + length($replace)); }` [download] In this case, an `s///` regex is actually 5% faster.	[reply] [d/l] [select]
Re: Answer: How do I replace a substring (if exists) with a different substring in a string? by kocetoo (Novice) on Jun 28, 2016 at 12:38 UTC
actually you can change: `substr( $string, $pos, $length( $find ), $replace );` [download] with this one: `substr( $created, $pos, length( $find ), $replace );` [download] `$length` is not function!!!	[reply] [d/l] [select]

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