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Operador Ternario Python 3 Full Correctness Of

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In the front, its a ternary conditional operation, and requires the else. Cheers.

That documentation doesnt even include the term ternary, so you would be hard-pressed to find it via Google unless you knew exactly what to look for.

The version 2 documentation is somewhat more helpful and includes a link to PEP 308, which includes a lot of interesting historical context related to this question.

If condition evaluates to True, then a is evaluated and returned but b is ignored, or else when b is evaluated and returned but a is ignored.

This means you cant use assignment statements or pass or other statements within a conditional expression.

It is very useful when youre in a one value or another situation, it but doesnt do much else.

For example, x 4 if b 8 else 9 is read aloud as x will be 4 if b is greater than 8 otherwise 9.

You may also understand it as do A in most case, except when C then you should do B instead.

If x2 and y1, you might expect that to yield 4, but it would actually yield 1.

Operador Ternario Python 3 Mod Is Used

A convincing argument is the operator, mimicking the way mod is used in math would have been a disaster.

Also, for safety you can explicitly test for truthiness by writing bool( ).

It also shows that more than one ternary can be chained together into a single expression.

This could be suboptimal or even buggy (i.e.

Value and falseValue could be methods and have side-effects).

In addition, it doesnt solve the case when using properties.

If you want this behavior the method is OK, otherwise use this.

A workaround is to replace cond with cond is not None in these cases, although that is not a perfect solution.

As highlighted by AndrewCecil, blob is truthy but it is not True.

If ontrue and onfalse are expensive to call this is a bad answer.

And because of the recursive definition, you can chain them indefinitely (though it may considered bad style.).

People learning list comprehensions and generator expressions may find this to be a difficult lesson to learn - the following will not work, as Python expects a third expression for an else.

So the above is either an incomplete piece of logic (perhaps the user expects a no-op in the false condition) or what may be intended is to use expression2 as a filter - notes that the following is legal Python.

However, a common and performant Pythonic idiom for this use-case is to use or s shortcutting behavior.

Note that some style-guides may limit this usage on the grounds of clarity - it does pack a lot of meaning into very little syntax.

I learned the hard way, so your way might not be as hard.;) Using if without the else, at the end of a generator expression or list comprehension will filter the iterable.

In the front, its a ternary conditional operation, and requires the else.