[Python-Dev] Re: [Patches] [Patch #101175] Fix slight bug in the Ref manual docs on listcomprehensions (original) (raw)

Tim Peters tim_one@email.msn.com
Tue, 15 Aug 2000 21:26:36 -0400

[Tim]

[x if 6] should not be a legal expression but the grammar allows it today.

[Greg Ewing]

Why shouldn't it be legal?

Because Guido hates it. It's almost certainly an error on the part of the user; really the same reason that zip() without arguments raises an exception.

... Excluding it will make both the implementation and documentation more complicated,

Of course, but marginally so. "The first clause must be an iterator"; end of doc changes.

with no benefit that I can see.

Catching likely errors is a benefit for the user. I realize that Haskell does allow it -- although that would be a surprise to most Haskell users .