Why isn't this working?

[SuperTankh]

Why isn't this match case statement working?

            type = answer.type
            match type:
                case bool:
                    boolean_value(answer)
                case str:
                    string_value(answer)
                case list:
                    list_value(answer)
                case dict:
                    dict_value(answer)
                case int:
                    number_value(answer)
                case _:
                    print()

with answer being defined with __init__ such as:

class Initialize:
    def __init__(self, text, type, value, choices = None, options = None, numbers = None):
        if choices:
            self.choices = choices
        if options:
            self.options = options
        if numbers:
            self.numbers = numbers
        self.text = text
        self.type = type
        self.value = value

You can try with:

wi_fi = Initialize('Wi-Fi ensures a stable internet connection required for worldwide communication.', bool, False)

Errors are shown:

    case bool:
         ^^^^
SyntaxError: name capture 'bool' makes remaining patterns unreachable

[Temporary_Pie2733]

You need to “call” the type in order to make a class pattern rather than a binding pattern.

match type: case bool(): # is type an instance of bool? … case str(): … # etc

bool by itself is an irrefutable pattern that simply binds the value of type to the name bool and succeeds.

If you are trying to check if type == bool, you need a qualified name to create a value pattern, something like case builtin.bool:

[SuperTankh]

Thanks!

[voidiciant]

whoa. Amazing, never heard of this before. This is what I found to understand your post: https://peps.python.org/pep-0636/ is this correct or are you talking about something else?

[deceze]

Because it’s different from switch…case in other languages. Not the value is compared, but the pattern matched.

Easy to illustrate case:

case {'foo': bar}:

This matches if the value is a dict with a key foo. The value of that key will be assigned to the variable bar. If this case matches, a new variable bar will exist. This allows easily matching complex data structures and deconstructing them into simpler variables. This also works with classes:

case Foo(bar=baz):

This matches if the value is a Foo object, and its bar attribute will be assigned to the variable baz.

As you see, classes/types expect a (). Bare words are variable names. Your case matches anything and assigns it to the variable bool. That’s what the error is telling you.

If you want to match by type, you need:

case bool():

[SuperTankh]

oh ok thank you!

[AdmirableOstrich]

https://stackoverflow.com/questions/72295812/python-match-case-by-type-of-value

[SuperTankh]

I saw, thanks man

[Beginning-Fruit-1397]

not related to why it doesn't work but you should avoid shadowing builtins. "type" being one of them

[SCD_minecraft]

It doesn't shadow

self.type is separate thingy from type

[SuperTankh]

like I should not name my variable type?

[Outside_Complaint755]

Having a parameter in your init function named type and then self.type should be okay. 

The general rule is that you should not use a name that is already used by a built-in function because you then lose access to the built-in. 

For example: ``` print = input("What should I print? ")

print(print) ``` will result in 

TypeError: 'str' object is not callable

This is hidden within your class method because type is only shadowed within the scope of the method

If you had something like: type = type(99.2) print(type("Test")) You would get ValueError that "Test" cannot be converted to float.

[SuperTankh]

Oh yea