Why should we use - gt; in def __init__(self, n) - gt; None:? 2 In python 3 5 appeared type annotation option def __init__(self, n) -> None: means that __init__ should always return NoneType and it can be quite helpful if you accidentally return something different from None especially if you use mypy or other similar things But you can ignore it if you prefer the old way to do it
. def files C C++ DLLs - Stack Overflow The advantage of def file is that, it helps you to maintain the backword compatibility with the already realsed dlls i e it maintains the ordinal numbers for apis Suppose you add a new api in the dll, then the linker looks at your def file genearate the ordinal number for the ne wapi such that the ordinal numbers for the old apis are intact
python - Why do some functions have underscores - Stack Overflow The other respondents are correct in describing the double leading and trailing underscores as a naming convention for "special" or "magic" methods While you can call these methods directly ([10, 20] __len__() for example), the presence of the underscores is a hint that these methods are intended to be invoked indirectly (len([10, 20]) for example) Most python operators have an associated
Groovy: whats the purpose of def in def x = 0? However, variables defined using the keyword "def" are treated as local variables, that is, local to this one script Variables without the "def" in front of them are stored in a so called binding upon first use You can think of the binding as a general storage area for variables and closures that need to be available "between" scripts
function - what is def in Java class - Stack Overflow while googling, I find that "def" is used in python and groovy language But, I am using java So, how come it is possible to use keywords like "def" in java class? Is it possible to use other programming languages keywords in java? Please let me know in comment section, if you need any information from my end Any help would be appreciated