counter ( variable -- n ) (original) (raw)

counter ( variable -- n )

Vocabulary
namespaces

Inputs

variable a variable, by convention a symbol

Outputs

n an integer

Word description
Increments the value of the variable by 1, and returns its new value.

Notes
This word is useful for generating (somewhat) unique identifiers. For example, the gensym word uses it.

Side effects
Modifies variable

Definition

USING: kernel math ;

IN: namespaces

: counter ( variable -- n ) [ 0 or 1 + dup ] change-global ;
inline