Wikipedia said:
Never mind, I'm an idiot, you didn't actually ask how they came up with it, but the name....
.... Which, of course, the bbcode reader eats... Sigh."icode" should prevent that.Also, for the Elvis emoticon I think it's missing an o. ?
Fair enough, lol
Wikipedia said:
:= and used to assign a variable in a statement. if func(var):
print(func(var))
#or:
if new := func(var):
print(new)Hence the famous yoda-condition pattern :
if (<constant> == <variable>) { ... }= you'll get an error at compile time.Your concern is sensible. AFAIK, modern C compilers can emit warning in case of assignation in test expression. That's probably to be prefered.
If you read PEP 572, it gives some specific use cases where it results in cleaner code. One of them is reading binary files which is where I have used it.
while (data := binary_file.read(4)):
process(data)data = binary_file.read(4)
while (data):
process(data)
data = binary_file.read(4)I think all of the major compilers warn about this by default now. The idiom is that if you really want an assignment, you indicate it by using double parentheses.
func returns a value intepretable as bool (eg std::optional<T>), I do like going...if(auto x = func()) {
doSomething(*x);
}== is a true abomination. So much so they had to invent === to get around it. if (condition1 && condition2 || !!condition3) {
}not instead of '!'. Also 'and' and 'or', makes for nicer looking code IMHO.
if data := func() and condition:
do_thing(data)
# is actually
if data := (func() and condition):
# data is True/False, not func return
# so do:
if (data := func()) and condition:I think you mean APL... After all, the problem with Perl is that it has decidedly non-clever syntax and semantics.
I've started doing the same. I was specifically worried about the old & instead of &&, or | instead of ||. Actually got flagged in a code review once because someone didn't know you could use 'and' and 'or' instead of && and ||. The history of those is actually kind of interesting. They're in the language primarily because of the need to support some character sets that didn't have & or | in them.
That right there is a damned good reason to never use the walrus. Most of the time I spend reading code, so it should be absolutely clear what it does in detail. When speed reading through code, that difference is subtle enough that I might miss it.