`declare -f "a="' fails unnecessarily

[Emanuele Torre]

`declare -f "something="' fails with the following error:

    $ declare -f 'a=x'
    bash: declare: cannot use `-f' to make functions
    $ f=a=x
    $ decalre -f -- "$f"
    bash: declare: cannot use `-f' to make functions

That error is not very useful. Bash makes `declare -f' fail with that
error when an argument looks like an assignment.

Since, in Bash, it is permitted to define functions that have names that
look like an assignments, I think it would make more sense if it would
just look for that function, instead of failing unnecessarily.

    $ function axb { printf hi\\n; }
    $ function a=b { printf hi\\n; }
    $ if declare -f 'axc' > /dev/null; then echo defined; else echo undefined;fi
    defined
    $ if declare -f 'abc' > /dev/null; then echo defined; else echo undefined;fi
    undefined
    $ if declare -f 'a=c' > /dev/null; then echo defined; else echo undefined;fi
    bash: declare: cannot use `-f' to make functions
    undefined
    $ if declare -f 'a=b' > /dev/null; then echo defined; else echo undefined;fi
    bash: declare: cannot use `-f' to make functions
    undefined

 emanuele6