Function names not as permissive as bash function names about shellcheck

[koalaman]

Interestingly, ? is valid when doing function foo? { ...; } but not with foo?() { ...; }.

[worr]

Your first example won't declare a function. You need the () after the name if you omit function when declaring the function.

Also, contrary to your examples, I've been doing:

?() {
    /bin/true
}

...() {
    /bin/true
}

Both are valid, however they totally break the parser.

[koalaman]

function is not omitted in the first example. It's right there. Your examples work for me in a script, but not in an interactive shell:

vidarh@vidarh 15:51 ~ $ cat foo

echo $BASH_VERSION
?() {
  echo foo
}
?

vidarh@vidarh 15:51 ~ $ bash foo
4.2.25(1)-release
foo
vidarh@vidarh 15:51 ~ $ source foo
4.2.25(1)-release
bash: ?(): command not found
foo
bash: foo: line 6: syntax error near unexpected token `}'
bash: foo: line 6: `}'
vidarh@vidarh 15:51 ~ $ 

[koalaman]

83c3dd3 accepts periods and question marks in function names. I'll leave 'function foo' vs 'foo()' in interactive mode for another time.