in reply to replace all numerics to words in a txt file

  1. When using capture groups, refer to them via $1, $2 etc.
  2. To evaluate code in the replacement part of substitution, use /e .
  3. You probably need + to match numbers > 9: 
    s/(\w+)/num2en($1)/ge

    [download]
    ($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]

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