[Python-ideas] A "local" pseudo-function

[Ken Hilton]

 > local { m = re.match(regexp, line)
>            if m:
>                print(m.group(0))
>       }

Or how about making "local" a pseudo-statement of sorts?

    local (m=re.match(exp, string)) {
        if m:
            print(m.group(0))
    }

The grammar would be as follows:

    local_stmt = "local" "(" local_assignments [ "," local_assignments ...
] ")" "{" BLOCK "}"
    local_assignments = NAME "=" EXPR

There would be no question about the scope of things in BLOCK - the
variables would disappear after the closing "}".
I say "pseudo"-statement because I'm wondering if something like this would
be legal:

    things = list(map(lambda m: local (gp1=m.group(1)) {
        result = gp1 + ''.join(reversed(gp1))
        result += gp1.replace('some', 'thing')
        return result
    }, re.finditer(exp, string)))

I'm thinking specifically about the "lambda m: local (...) {...}". If that
was made legal, it would finally allow for full-fledged anonymous
functions. Indeed, the "local" (statement?) itself is actually almost
equivalent to defining an anonymous function and executing it immediately,
i.e. this:

    (lambda x=5: x*x)()

would be equivalent to this:

    local (x=5) {
        return x * x
    }

both evaluating to 25.

Just some random thoughts!

Sincerely,
Ken
​ Hilton​
;
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