Re^2: How can I expand my substring?

$string1='--------NNNNNNN--------NNNNN--------NNNNN------NNNNNNN------
+-------BBBBB-----';
[download]

should become

 
$string1_new='--------NNNNNNN--------NNNNN--------NNNNN------NNNNNNNBB
+BBBBBBBBBBBBBBBBBBBBB';
[download]

$string2='---------NNNNN-NNNNNNNNNNNNN----NNNNNNNNNNN---------BBBBBBBB
+BB';
[download]

should become

$string2_new='---------NNNNN-NNNNNNNNNNNNN----NNNNNNNNNNNBBBBBBBBBBBBB
+BBBBBB';
[download]

$string3='-------NNNNNNN-----------------BBBBBBBBBBBBBBB-------------N
+NNNNNN';
[download]

should become

$string3_new='-------NNNNNNNBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
+BBBNNNNNNN';
[download]

$string4='--------BBBBBBBBBBBB-------NNNNNNNNNNNNN------NNNNNN';
[download]

should become:

$string4_new='--------BBBBBBBBBBBBBBBBBBBNNNNNNNNNNNNN------NNNNNN';
[download]

Does this make more sense? Thank you for the answer, I just don't get this "1" that you have there... I tried the:

    $initial_protein=~s/B-/BB/g;
    $initial_protein=~s/-B/BB/g;
[download]

but didn't work...

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Re^3: How can I expand my substring? by Corion (Patriarch) on Jun 30, 2014 at 12:02 UTC
The "1" has significance, in the sense that it is the loop body. You could rewrite my code as: `while( $string1 =~ s/B-/BB/ or $string1 =~ s/-B/BB/ ) { # Replacement already happened in the while condition };` [download] There are other ways, but I find this approach to be closest to your description.	[reply] [d/l]
Re^4: How can I expand my substring? by Anonymous Monk on Jun 30, 2014 at 12:10 UTC
Oups, I think it misses case 4 or not? I mean, if the string starts with --- and doesn't have any NNNN before the BBB, then the BBB should be expanded only to the right (if there is space).	[reply]
Re^5: How can I expand my substring? by Corion (Patriarch) on Jun 30, 2014 at 12:17 UTC
Ah, I misread that part of the specification. Most likely, the easiest approach is now to do replacement with `/e` and look-ahead and look-behind: `# Expand string to the left $string4 =~ s!(?<=N)(-+)(?=B)!'B' x length $1!e; # Expand string to the right $string4 =~ s!(?<=B)(-+)!'B' x length $1!e;` [download]	[reply] [d/l] [select]
Re^6: How can I expand my substring? by Anonymous Monk on Jun 30, 2014 at 12:24 UTC
Re^7: How can I expand my substring? by Corion (Patriarch) on Jun 30, 2014 at 12:33 UTC
Some notes below your chosen depth have not been shown here
Re^6: How can I expand my substring? by Anonymous Monk on Jul 22, 2014 at 13:04 UTC
Re^7: How can I expand my substring? by Corion (Patriarch) on Jul 22, 2014 at 13:11 UTC
Some notes below your chosen depth have not been shown here
Re^4: How can I expand my substring? by Anonymous Monk on Jun 30, 2014 at 12:07 UTC
Thanks Corion! Works smoothly!	[reply]