/usr/share/doc/m4/examples/capitalize.m4 is in m4 1.4.17-2ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 | divert(`-1')
# upcase(text)
# downcase(text)
# capitalize(text)
# change case of text, simple version
define(`upcase', `translit(`$*', `a-z', `A-Z')')
define(`downcase', `translit(`$*', `A-Z', `a-z')')
define(`_capitalize',
`regexp(`$1', `^\(\w\)\(\w*\)',
`upcase(`\1')`'downcase(`\2')')')
define(`capitalize', `patsubst(`$1', `\w+', `_$0(`\&')')')
divert`'dnl
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