Equate Statements

Equate statements enable the programmer to define a symbol by assigning it a value. This value may be a reference to another symbol, register name, or expression. In equate statements, a symbol can be defined only once throughout the source file. These symbols may have forward references, except when referencing a register name. A symbol name defined in an equate statement cannot be defined in an assignment statement.

Equate statements have the same syntax as assignment statements, except for the operator.

There are two types of equate statements:

symbol equate statements
register equate statements

Symbol Equate Statements

A symbol equate statement has the following syntax:

identifier==expression // comments

Where:

identifier	Represents a symbol in the symbol name space.
expression	Specifies the type and value of the identifier. The expression can contain forward references.

The following is an example of an equate statement that defines a symbol:

A == 5

Register Equate Statements

A register equate statement has the following syntax:

identifier==register name // comments

Where:

identifier	Represents a register name in the symbol name space.
register name	Specifies an alternate register name. The register name cannot contain forward references. If the register name is a stack or rotating register name, the new register name continues to refer to the previously-defined register, even if the name is no longer in effect. See the Register Stack Directive and Rotating Register Directives sections.

The following is an example of an equate statement that defines a register name:

A == r1