[Python-ideas] Combining test and assignment (original) (raw)

Serhiy Storchaka storchaka at gmail.com
Sun Jan 22 19:02:40 CET 2012

22.01.12 14:04, Paul Moore написав(ла):

While in general I agree with you, there is a natural reading of this:

"if spam() isn't 'ham', frobulate it" The fact that you have to choose a name is because computer languages have to be more explicit than natural languages, and can't deal with the implicit referent involved in the English usage of "it". The need for assignment comes from the need for a name. You could actually deal with the if-or-while-expression-assignment case by defining a special variable it to mean the value of the condition in the containing if or while expression, but it has all the same lack of generality issues as any proposal that limits itself to if/while conditions. And short of explicitly marking the expression somehow, you can't generalise any further.

Kotlin (http://confluence.jetbrains.net/display/Kotlin/Kotlin) has "it":

names filter {it.startsWith("A")} sortby {it} map {it.toUpperCase()} foreach {print(it)}

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