in reply to Remove whitespace in string and maintain overall length

Use tr to squelch the spaces; and the return value plus a little math to pad to the required length:

$s = 'fred  bill   john';;

$s .= ' 'x ( 37 - length( $s ) + $s =~ tr[ ][]s ); 

print "'$s'";;
'fred bill john                         '

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