Kristján Valur Jónsson wrote:
Are you all certain that this mapping from a generator expression to
a foor loop isn't just a happy coincidence?
Yes, The manual *defines* the meaning of a comprehension in terms of the
corresponding nested statements.
"The comprehension consists of a single expression followed by at least
one for clause and zero or more for or if clauses. In this case, the
elements of the new container are those that would be produced by
considering each of the for or if clauses a block, nesting from left to
right, and evaluating the expression to produce an element each time the
innermost block is reached." (3.0 doc)
It was originally defined as exactly equivalent (with empty list
initialization added). The only intended change of the slightly softer
newer version is that the target name bindings do not escape the scope
of the comprehension.
The proposed change would BREAK the definition and intent of what a
comprehension means.
> After all, the generator statement is just a generalization
> of the list comprehension
I would call it a variation. Syntactically, a generator statement is a
comprehension with parentheses instead of square brackets or curly braces.
tjr
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