@x [2.23] l.723 - Translate characters if desired, otherwise allow them all.
for i:=0 to @'37 do xchr[i]:=' ';
for i:=@'177 to @'377 do xchr[i]:=' ';
@y
{Initialize |xchr| to the identity mapping.}
for i:=0 to @'37 do xchr[i]:=i;
for i:=@'177 to @'377 do xchr[i]:=i;
@z