Equals (computing)
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"=", ASCII character 61.
Common names: ITU-T: equals; gets; takes. Rare: quadrathorpe; INTERCAL: half-mesh.
The equal sign is used in many programming languages, such as BASIC and C as the assignment operator. Other languages, such as Ada and Pascal, use variants such as := ("becomes equal to") to avoid upsetting mathematicians with statements such as "x = x+1" (and to avoid common typos in comparisons that can happen in languages that consider assignment to be an operator that may be used anywhere in an expression. e.g., the = – == confusion in C). In these languages the := is not considered an operator and may only occur between the variable and the expression of the assignment.
It is also used by itself and in compounds such as <=, >=, ==, /=, != for various comparison operators, and in C's +=, *= etc. which mimic the primitive operations of two-address code.
Many languages have different equality predicates, operators which test the equality of values. For instance, Perl has the numerical equality operator == and the string equality operator eq.
Equality is a property of values, not objects. An operator which asks if two variables refer to the same data object is an identity predicate, such as Python's is or Common Lisp's EQ.
