PFE 0.33.70

generated
(C) Guido U. Draheim
guidod@gmx.de

Locals

+ extensions

---

(LOCAL)  => "[ANS] FORTH"

(no description)

primitive code = [p4_paren_local]

---

LOCALS|( xN ... x2 x1 [name1 .. nameN <|>] -- )  => "[ANS] FORTH"

create local identifiers to be used in the current definition. At runtime, each identifier will be assigned a value from the parameter stack. The identifiers may be treated as if being a VALUE , it does also implement the ansi TO extensions for locals. Note that the identifiers are only valid inside the currently compiled word, the SEE decompiled word will show them as <A> <B> ... <N> a.s.o. see also LVALUE

compiling word = [p4_locals_bar]

---

LVALUE( value [name] -- )  => "EXTENSIONS"

declares a single local VALUE using (LOCAL) - a sequence of LVALUE declarations can replace a LOCALS| argument, ie. LOCALS| a b c | is the same as LVALUE a LVALUE b LVALUE c . This should also clarify the runtime stack behaviour of LOCALS| where the stack parameters seem to be assigned in reverse order as opposed to their textual identifier declarations. compare with VALUE and the pfe's convenience word VAR.

  : LVALUE 
    STATE @ IF 
      VALUE 
    ELSE 
      BL WORD COUNT DUP (LOCAL) (TO)
    THEN
  ; IMMEDIATE
  

compiling word = [p4_local_value]

---

LBUFFER:( size [name] -- )  => "EXTENSIONS"

declares a single local VALUE using (LOCAL) - which will hold the address of an area like BUFFER: but carved from the return-stack (as in C with alloca). This local buffer will be automatically given up at the end of the word. The return-stack-pointer will be increased only at the time of this function (and the address assigned to the LVALUE) so that the provided size gets determined at runtime. Note that in some configurations the forth-return-stack area is quite small - for large string operations you should consider to use a POCKET-PAD in pfe.

  : LBUFFER:
    STATE @ IF 
      BUFFER:
    ELSE 
      :NONAME ( size -- rp* ) R> RP@ - DUP RP! SWAP >R ;NONAME
      COMPILE, POSTPONE LVALUE
    THEN
  ; IMMEDIATE
  

compiling word = [p4_local_buffer_var]