title: TO
description:

ANS Forth (1994) allows TO to be used on children of VALUE and locals.
This section extends the specification of this word:
TO is allowed to work on children of DEFER .

Proposal:
              Change the current definition of
              6.2.2295 TO,
              13.6.1.2295 TO,
              modify 4.1.2 "Ambiguous conditions",
              Table 9.2 "THROW code assignments",
              to say the following:

----

6.2.2295   TO                               CORE EXT

Interpretation: ( x "<spaces>name" -- )

 Skip leading spaces and parse _name_ delimited by a space.

 If _name_ is a deferred word or a value, set _name_ to _x_.
 If _name_ is a deferred word, an ambiguous condition exists
 if _x_ is not a valid execution token.

 An ambiguous condition exists if _name_ is of type not recognized by TO.

Compilation: ( "<spaces>name" -- )

 Skip leading spaces and parse _name_ delimited by a space.
 If _name_ is a deferred word or a value, append the
 run-time semantics given below to the current definition.

 An ambiguous condition exists if _name_ is of type not recognized by TO.

Run-time: ( x -- )

 Set _name_ to _x_.
 If _name_ is a deferred word, an ambiguous condition exists
 if _x_ is not a valid execution token.

 Note: An ambiguous condition exists if either POSTPONE or [COMPILE]
 is applied to TO.

See: 6.2.2405 VALUE, ?.?.???? DEFER, 13.6.1.2295 TO, ?.?.???? IS.

----

13.6.1.2295   TO                                            LOCAL
 Extend the compilation semantics of 6.2.2295 TO to include:

Compilation: ( "<spaces>name" -- )

 If _name_ was defined by (LOCAL), append the
 run-time semantics given below to the current definition.

 Note: Due to the locals' privileged position in the search order,
 naming conflicts are resolved in favour of locals.

Run-time: ( x -- )

 Set _name_ to _x_.

 Note: An ambiguous condition exists if either POSTPONE or [COMPILE]
 is applied to TO.

 See: 3.4.1 Parsing, 6.2.2295 TO, 6.2.2405 VALUE, ?.?.???? DEFER,
 13.6.1.0086 (LOCAL).

----
4.1.2 Ambiguous conditions

Remove:
  - name not defined by 6.2.2405 VALUE used by 6.2.2295 TO;

Add:
  - name of type not recognized by 6.2.2295 TO used with TO;

  - storing an invalid execution token into a deferred
  word (6.2.2295 TO)

----
Table 9.2 - THROW code assignments

  -60 execution of a deferred word associated with an invalid execution token

Experience:
   Many years of use in OpenBoot and OpenFirmware systems.

Comments:
     See PROPOSALS for DEFER, BEHAVIOR.
See:
~~~tag[a href=to.txt]tag~~~ANSI TC discussion~~~tag[/a]tag~~~