dnl ../doc/m4.texinfo:2809: Origin of test
eval(-3 * 5)
dnl @result{}-15
eval(index(`Hello world', `llo') >= 0)
dnl @result{}1
define(`square', `eval(($1)**2)')
dnl @result{}
square(9)
dnl @result{}81
square(square(5)+1)
dnl @result{}676
define(`foo', `666')
dnl @result{}
eval(`foo'/6)
dnl @error{}51.eval:14: m4: Bad expression in eval: foo/6
dnl @result{}
eval(foo/6)
dnl @result{}111