Other notes

Bengt Richter bokr at oz.net
Thu Dec 30 05:46:25 CET 2004


On Thu, 30 Dec 2004 03:37:38 GMT, Andrew Dalke <dalke at dalkescientific.com> wrote:

>Bengt Richter:
>> OTOH, there is precedent in e.g. fortran (IIRC) for named operators of the
>> form .XX. -- e.g., .GE. for >= so maybe there could be room for both.
>
>> Hm, you could make
>> 
>>      x .infix. y
>
>
>>   x .op1. y .op2. z => op2(op1(x, y), z)
>
>The problem being that that's already legal syntax
D'oh ;-)

>
>>>> class Xyzzy:
>...   def __init__(self):
>...     self.op1 = self.op2 = self.y = self
>...     self.z = "Nothing happens here"
>... 
>>>> x = Xyzzy()
>>>> x .op1. y .op2. z
>'Nothing happens here'
>>>> 

Ok, well, that's happened to me before ;-)
We'll have to find a way to make it illegal, but it's not likely to be quite as clean.

    x ..OP y
    x ./OP y
    x .<OP y
    x .<OP>. y
    X ._OP_. y 
    x ..OP.. y # for symmetry ;-)

    X .(OP). y # emphasizes the .expression. returning a function accepting two args

That might be the best one.

OTOH some time ago I was thinking of .(statements). as a possible tokenizer-time star-gate into
a default-empty tokenizer-dynamically-created module which would essentially exec the statements
in that module and return the value of the last expression as a string for insertion into the token
source code stream at that point being tokenized.

Thus e.g. you could have source that said

    compile_time = .(__import__('time').ctime()).

and get a time stamp string into the source text at tokenization time.

I had also thought obj.(expr) could be syntactic sugar for obj.__dict__[expr]
but that would also interfere ;-)

So maybe .(OP). should for infix, and .[stargate exec args]. should be for that ;-)

Regards,
Bengt Richter



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