Ned Batchelder writes:
> "lambda" is unnecessarily obscure.
And it should be. It's really only useful as an argument. There's no
advantage to
foo = (x) -> 1
vs.
def foo(x): return 1
except a couple of characters. So what currently looks like
some_list.sort(key=lambda e: e[3].priority)
would then be
some_list.sort(key=(e)->e[3].priority)
which is shorter but not particularly more readable (and already has a
familiar meaning in C-like languages). It seems to me that two
changes to def might be considered:
1. In a one-line def of the form "def foo([arglist]): return EXPR",
"return" may be omitted, and the function returns the value of
EXPR (rather than None as currently). (As a multiline def, EXPR
would be presumed to be evaluated for side effects, and
2. As an actual argument, a one-line def is interpreted not as a
positional argument, but as a keyword argument, so that in
some_list.sort(def key(e): e[3].priority)
the name "key" is not optional, and must match a keyword argument.
I suggest 1 for "ordinary" defs as well for consistency, but evidently
we could also restrict that usage to "def as keyword argument", and
maintain backwards compatibility.
2 could even be independent of 1:
some_list.sort(def key(e): return e[3].priority)
but that seems excessively verbose.
Another possible use case would be in a for loop:
for fun in [def fun(): return 1,
def fun(): return 2,
def fun(): return 3]:
do_something_with(fun)
where similarly the loop variable needs to match the def.
> Beginner: "why is it called lambda?"
>
> Teacher: "Don't worry about it, just use it to define a function"
>
It me. But it would go like this:
Teacher [face lights up at the chance to talk math history]: "You see, ..."
Students [in harmony]: "NOOOOOOOOooooooo.......... :-(" [collective sigh]
Regards,
Steve
_______________________________________________
Python-ideas mailing list -- [email protected]
To unsubscribe send an email to [email protected]
https://mail.python.org/mailman3/lists/python-ideas.python.org/
Message archived at
https://mail.python.org/archives/list/[email protected]/message/2UQU33XFZFMNP4AITJXQJI3UNPYTEOW7/
Code of Conduct: http://python.org/psf/codeofconduct/
