m4_dnl To avoid annoying conflicts with quote characters, use
m4_dnl U+2068 FIRST STRONG ISOLATE and U+2069 POP DIRECTIONAL ISOLATE
m4_changequote(⁨,⁩)

m4_define(
	m4_footer,
	⁨m4_define(⁨m4___caller__⁩, m4___file__)m4_include(footer.html)⁩
)

m4_define(
	m4_fmt_code,
	⁨m4_esyscmd(fmt-code "$1" m4___file__)m4_dnl⁩
)