Function
A function produces a return value from a list of argument values.
Related concepts: OperatorParameterArgumentReturnMethod
Closest Wikipedia entry: Subroutine
Misconceptions about Function15 documented Misconceptions
Check Yourself
OutsideInMethodNesting — Java
Nested method calls are invoked outside in
ArrowFunctionNoImpliedReturn — JavaScript
Even when an arrow function consists just of an expression, the return keyword must be explicitly written
ArrowFunctionRequiresFunctionKeyword — JavaScript
Arrow functions also require the keyword 'function'
CallbackParametersInCaller — JavaScript
Parameters of a callback function may be written as parameters of the caller function
FunctionAsValueWithParentheses — JavaScript
To use a function as a value, one needs to have parentheses after its name
FunctionOverloading — JavaScript
It is possible to create multiple functions with the same name but with different signatures
FunctionsCannotBeImmediatelyInvoked — JavaScript
Functions cannot be called in the expression in which they are defined
FunctionsMustBeNamed — JavaScript
Every function definition requires an associated name
NoFunctionCallsChaining — JavaScript
It is not allowed to chain function calls
NumberOfParametersMatchArguments — JavaScript
Functions must be called with the same number of arguments as defined in their signature
DeferredReturn — Python
A return statement in the middle of a function doesn't return immediately
MultipleValuesReturn — Python
Functions can return multiple values
OutsideInFunctionNesting — Python
Nested function calls are invoked outside in
ParenthesesOnlyIfArgument — Python
() are optional for function calls without arguments
ReturnCall — Python
Return statements need () around the return value