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I want to be able to pass arguments like this: 

fn(a>=b) or fn(a!=b)

I saw this behavior in DjangoORM and SQLAlchemy but I don't know how to achieve it.

jonrsharpe
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user3485236
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    It's not quite what you're asking for, but in the general case you can pass e.g. `operator.ne` (for `!=`) and `operator.gt` (for `>`) around – jonrsharpe Oct 04 '15 at 13:41

1 Answers1

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ORMs use special methods on classes for a and b to hook into operators and customise what is produced.

>= for is handled by the object.__ge__() method, while != calls object.__ne__().

Typically, the ORM object used for a returns a new object with the operation applied, allowing you to chain operations, and the fn() function expects such an ORM object and will read the operation status from there.

Martijn Pieters
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