Void type null constant - MQL4

Void Type and NULL Constant

The void type is a fundamental MQL4 type.

It signifies that a function returns no value.

When used as a function parameter, void denotes the absence of parameters.

NULL is a predefined constant variable of the void type.

It can be assigned to variables of any fundamental type without explicit conversion.

Comparisons between fundamental type variables and NULL are permitted.

NULL can also be compared to pointers to objects created with the new operator.

// If the string is not initialized, then assign our predefined value to it
if(some_string == NULL) some_string = "empty";

[Variables](/basis/variables)

[Functions](/basis/function)

[Typecasting](/basis/types/casting)

[User-defined Types](/basis/types/typedef)