return statements in lambda
from "Python for Lisp Programmers": http://www.norvig.com/python-lisp.html
Don't forget return. Writing def twice(x): x+x is tempting and doesn't signal a warning or > ception, but you probably meant to have a return in there. This is particularly irksome because in a lambda you are prohibited from writing return, but the semantics is to do the return.
maybe adding an (optional but encouraged) "return" to lambda would be an improvement? lambda x: x + 10 vs. lambda x: return x + 10 or is this just more confusing... opinions? </F>
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maybe adding an (optional but encouraged) "return" to lambda would be an improvement?
lambda x: x + 10
vs.
lambda x: return x + 10
or is this just more confusing... opinions?
It was an odd complaint to begin with, since Lisp-heads aren't used to using "return" anyway. More of a symptom of taking a shallow syntactic approach to a new (to them) language. For non-Lisp heads, I think it's more confusing in the end, blurring the distinction between stmts and expressions ("the body of a lambda must be an expression" ... "ok, i lied, unless it's a 'return' stmt). If Guido had it to do over again, I vote he rejects the original patch <wink>. Short of that, would have been better if the lambda arglist required parens, and if the body were required to be a single return stmt (that would sure end the "lambda x: print x" FAQ -- few would *expect* "return print x" to work!). hindsight-is-great<wink>-ly y'rs - tim
participants (2)
-
Fredrik Lundh -
Tim Peters