[Python-ideas] f-string "debug" conversion

Anders Hovmöller boxed at killingar.net
Wed Oct 3 04:02:30 EDT 2018

>> Here’s the idea: for f-strings, we add a !d conversion operator, which 
>> is superficially similar to !s, !r, and !a. The meaning of !d is: 
>> produce the text of the expression (not its value!),
> I SO WANT THIS AS A GENERAL FEATURE, not just for f-strings, it hurts.
> Actually what I want is an executable object (a function?) which has the 
> AST and text of the expression attached. If putting this into f-strings 
> is a first step towards getting this thunk-like thing, then I don't 
> need to read any further, I'm +10000 :-)

Well... this is a trivial expansion of the keyword argument short form proposal you were very strongly opposed ^_-

So, I suggested `foo(=a)` as short form for `foo(a=a)`, but if we interpret it instead as `foo(=a)` -> `foo(**{'a': a}`, which is really the same thing for most purposes, then we could trivially get `foo(=1+3*bar)` -> 'foo(**{'1+3*bar': 1+3*bar})'

I'm fine with this proposal. And thanks Chris for the idea!

/ Anders

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