in reply to help with regex

You don't want to remove a slash, you want to replace two slashes by a single one. Use a different delimiter to avoid the need of backslashing: 
$test =~ s{^//}{/};

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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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