length()

Syntax

length(expr)

Returns length of the expression, the length of the string, the length of the integer part of the number, or length of the list

length(pi) => 1
length(pi*pi) => 1
length(pi^pi) => 2
length([]) => 0
length([1,2,3]) => 3
length('') => 0
length('foo') => 3