if ('p' eq substr $strTest, 4, 1) {
[download]

or index

if (4 == index $strTest, 'p', 4) {
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or, a bitmask:

if (($strTest & "\0\0\0\0\xff\0") eq "\0\0\0\0p\0") {
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($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,
[download]