Pascal : inverting a string with recursion -


i'm trying learn recursion in pascal, , have code invert string recursion : 

function invert (ch:string) : string;      begin      if ch=''      invert:=''      else       invert:=copy(ch,length(ch),1)+invert(copy(ch,1,length(ch)-1));     end;

can explain me what's going on here step step. thank you.

if string empty, inversion empty string; otherwise, inversion last character followed inversion of (the string minus last character).

fortunately, have function can invert string: invert.


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