Function Values

Function values are those that when invoked with a set of input values (i.e., arguments) produce a new value.

Structure

In M, functions are specified by listing the input parameters of the function in parentheses, then the “goes to” operator =>, then the expression that defines the function.

Examples

Concatenator = (parameter1, parameter2) => (parameter1 & parameter2)
DifferentDistinct = (x) => List.Difference(x,List.Distinct(x))

Related Functions

Given their inherent power and flexibility, function values have only five related functions – two pertaining to function creation, two pertaining to invoking custom functions, and one informational function to determine if a given function is a data source.

Special Considerations

• Flexibility and Power – Functions can be assigned to variables, passed as arguments, and returned from other functions, making them some of the most versatile and powerful kinds of values in M.
• Importance...