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Is there a way to expand a Python tuple into a function - as actual parameters?
For example, here expand() does the magic:
some_tuple = (1, "foo", "bar") def myfun(number, str1, str2): return (number * 2, str1 + str2, str2 + str1) myfun(expand(some_tuple)) # (2, "foobar", "barfoo") I know one could define myfun as myfun((a, b, c)), but of course there may be legacy code. Thanks
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This method of passing a tuple as an argument to a function involves unpacking method. Unpacking in Python uses *args syntax. As functions can take an arbitrary number of arguments, we use the unpacking operator * to unpack the single argument into multiple arguments.
The * operator simply unpacks the tuple (or any iterable) and passes them as the positional arguments to the function. Read more about unpacking arguments. The * operator simply unpacks the tuple and passes them as the positional arguments to the function.
You can't add elements to a tuple because of their immutable property. There's no append() or extend() method for tuples, You can't remove elements from a tuple, also because of their immutability.
A tuple can be an argument, but only one - it's just a variable of type tuple . In short, functions are built in such a way that they take an arbitrary number of arguments. The * and ** operators are able to unpack tuples/lists/dicts into arguments on one end, and pack them on the other end.
myfun(*some_tuple) does exactly what you request. The * operator simply unpacks the tuple (or any iterable) and passes them as the positional arguments to the function. Read more about unpacking arguments.
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Note that you can also expand part of argument list:
myfun(1, *("foo", "bar")) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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