isn't this cleaner than a full chain of shell variable(s) + declare + eval + single quote escapes + echo + pipe(s) + tr just to avoid a sub-shell or external process ?

# ***MUCH*** faster for ASCII only

mawk '$!NF = toupper($_)' <<< 'abcxyz' 

ABCXYZ

gawk '$_ = tolower($_)' <<< 'FAB-EDC'

fab-edc

isn't this cleaner than a full chain of shell variable(s) + declare + eval + single quote escapes + echo + pipe(s) + tr just to avoid a sub-shell or external process ?

# ***MUCH*** faster for ASCII only

mawk '$!NF = toupper($_)' <<< 'abcxyz' 

ABCXYZ

gawk '$_ = tolower($_)' <<< 'FAB-EDC'

fab-edc

and Unicodes are just as easy to work with, without having to "unpack" or "encode" or "decode" bytes

printf '%s' "${test_utf8}" | ……

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…… | gawk '$_ = toupper($_)'

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