6.2.2405
VALUE
 
CORE EXT
 
( x "<spaces>name" -- )

Skip leading space delimiters. Parse name delimited by a space. Create a definition for name with the execution semantics defined below, with an initial value equal to x.

name is referred to as a "value".

name Execution:
( -- x )

Place x on the stack. The value of x is that given when name was created, until the phrase x TO name is executed, causing a new value of x to be assigned to name.

TO name Run-time:
( x -- )

Assign the value x to name.

See:
3.4.1 Parsing, 6.2.2295 TO, A.6.2.2405 VALUE.

Rationale:
Typical use:
0 VALUE data

: EXCHANGE ( n1 -- n2 ) data SWAP TO data ;

EXCHANGE leaves n1 in data and returns the prior value n2.
Testing:
T{  111 VALUE v1 -> }T
T{ -999 VALUE v2 -> }T
T{ v1 ->  111 }T
T{ v2 -> -999 }T
T{ 222 TO v1 -> }T
T{ v1 -> 222 }T

T{ : vd1 v1 ; -> }T
T{ vd1 -> 222 }T

T{ : vd2 TO v2 ; -> }T
T{ v2 -> -999 }T
T{ -333 vd2 -> }T
T{ v2 -> -333 }T
T{ v1 ->  222 }T