Hi,

I came across these bits of code on StackOverflow the other day, both of which count the occurrence of a character in a string, and for the life of me, I don't understand what's going on, or why all those steps are necessary:

If the character is constant, the following is best: 
my $count = $str =~ tr/y//;

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If the character is variable, I'd use the following: 
my $count = length( $str =~ s/[^\Q$char\E]//rg );

[download]

Can anyone help me understand what's going on here?

map{$a=1-$_/10;map{$d=$a;$e=$b=$_/20-2;map{($d,$e)=(2*$d*$e+$a,$e**2
-$d**2+$b);$c=$d**2+$e**2>4?$d=8:_}1..50;print$c}0..59;print$/}0..20

[download]
Tom Melly, pm (at) cursingmaggot (stop) co (stop) uk

In reply to Confused by RegEx count by Melly

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