See also B::Deparse

$ cat junk
int( $ext eq "jpg"||"gif"||"bmp")

$ perl -MO=Deparse,-p junk
int(((($ext eq 'jpg') or 'gif') or 'bmp'));
junk syntax OK

$ perl -le " print int( 'jpg' eq 'jpg' ) "
1

$ perl -le " print int( 'gif' ) "
0

$ perl -le " print int( 'bmp' ) "
0
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