str % vals -like idea but for statements

[Dan Schmidt]

Beni Cherniavsky <cben at techunix.technion.ac.il> writes:

| On 2003-02-11, Dan Schmidt wrote:
|
|> I don't think I will ever fully get used to 'and' being of type
|>
|>   (bool, T) -> T
|>
| It's not.  It's (T, T) -> T!

Right :)  Or I guess more accurately it's (T1, T2) -> T1 | T2 (yecch)

| What a handy starting point.  I have had this new idea for the last days:
| I want the analog of ``str % vals`` for statements.
|
| [...]
|
| My proposal
| ===========
|
| Allow adding a class-like indented block of code to any simple statement,
| with the semantics that the block is evaluated first and the statement is
| the evaluated with the block's variables in scope.  Here is how you do a
| conditional expression morea readably with it::
|
|     print "Complex text about", n, things where:
|         if n == 1:
|             things = "thing"
|         else:
|             things = "things"
|     print "More code..."
|
| True, it's not more compact but it's more arguably more readable.

Haskell does this (with the same keyword) and I like it very much
there.  I would like it fine in Python too (though I don't really miss
it), but given Python's history and philosophy of keeping the language
small, I don't see much chance of it being added.

Dan

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