Re^11: How the auto-increment operator works?

Perhaps the best thing to do is to remember that in "magic" string incrementation, digit/lowercase/uppercase characters increment from right to left, wrap within themselves, and generate a "carry" into the next left column (or a new left column character if it's already the leftmost (update: and see LanX's reply concerning the "type" of a new column)) when they wrap:

increment left col ("carry") <- '0' -> '1' -> .. '9' (digits)
                                 ^                |
                                 |                |
                                 +----------------+

increment left col ("carry") <- 'a' -> 'b' -> .. 'z' (lower case)
                                 ^                |
                                 |                |
                                 +----------------+

increment left col ("carry") <- 'A' -> 'B' -> .. 'Z' (upper case)
                                 ^                |
                                 |                |
                                 +----------------+
[download]

String incrementation is pretty stable. I've never known it to change and I doubt it ever will (to preserve backward compatibility), so the best thing I can suggest is to experiment. Whatever results you get are the way "magic" string incrementation works.

c:\@Work\Perl\monks>perl -e "my $s = 'zZ9';  print qq{'$s' -> };  ++$s
+;  print qq{'$s'};"
'zZ9' -> 'aaA0'
c:\@Work\Perl\monks>perl -e "my $s = 'Zz9';  print qq{'$s' -> };  ++$s
+;  print qq{'$s'};"
'Zz9' -> 'AAa0'
c:\@Work\Perl\monks>perl -e "my $s = 'Zzzz9';  print qq{'$s' -> };  ++
+$s;  print qq{'$s'};"
'Zzzz9' -> 'AAaaa0'
c:\@Work\Perl\monks>perl -e "my $s = 'zzzz9';  print qq{'$s' -> };  ++
+$s;  print qq{'$s'};"
'zzzz9' -> 'aaaaa0'
c:\@Work\Perl\monks>perl -e "my $s = 'ZZZZ9';  print qq{'$s' -> };  ++
+$s;  print qq{'$s'};"
'ZZZZ9' -> 'AAAAA0'
[download]

Give a man a fish: <%-{-{-{-<

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Re^12: How the auto-increment operator works? by LanX (Saint) on Aug 02, 2020 at 16:02 UTC
> , and generate a "carry" into the next left column (or a new left column character if it's already the leftmost) when they wrap: Addendum: And the new left column will be of the same "type" like the old leftmost. `# leftmost is ... DB<14> $_="z"; print ++$_ # lowercase aa DB<15> $_="z9"; print ++$_ # ... aa0 DB<16> $_="zZ9"; print ++$_ # ... aaA0 DB<17> $_="Zz9"; print ++$_ # uppercase AAa0 DB<18>` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l]
Re^13: How the auto-increment operator works? by zapdos (Sexton) on Aug 02, 2020 at 23:26 UTC
Thank you too brother. ;-)	[reply]
Re^12: How the auto-increment operator works? by zapdos (Sexton) on Aug 02, 2020 at 07:48 UTC
God bless you for making this more clear to me. Domo arigato brother. ^__^	[reply]


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