--- gforth/kernel/vars.fs 1999/03/29 22:52:35 1.15 +++ gforth/kernel/vars.fs 2000/05/15 14:04:12 1.21 @@ -26,17 +26,22 @@ hex \ everything now hex! \ "a true flag ... [is] a single-cell value with all bits set" \ better definition: 0 0= constant true ( no dependence on 2's compl) -1 Constant true ( -- f ) \ core-ext -\G CONSTANT: @var{f} is a cell with all bits set. +\G @code{Constant} -- @i{f} is a cell with all bits set. \ see starts looking for primitives after this word! 0 Constant false ( -- f ) \ core-ext -\G CONSTANT: @var{f} is a cell with all bits clear. +\G @code{Constant} -- @i{f} is a cell with all bits clear. +[IFUNDEF] cell 1 cells Constant cell ( -- u ) \ gforth +\G @code{Constant} -- the number of address units corresponding to 1 cell. +[THEN] + 1 floats Constant float ( -- u ) \ gforth +\G @code{Constant} -- the number of address units corresponding to a floating-point number. -20 Constant bl ( -- c-char ) \ core -\G @var{c-char} is the character value for a space. +20 Constant bl ( -- c-char ) \ core b-l +\G @i{c-char} is the character value for a space. \ used by docon:, must be constant FF Constant /line @@ -45,7 +50,7 @@ FF Constant /line 10 Constant l/s 400 Constant chars/block -$20 8 2* cells + 2 + cell+ constant word-pno-size ( -- u ) +20 8 2* cells + 2 + cell+ constant word-pno-size ( -- u ) create holdbuf word-pno-size chars allot holdbuf word-pno-size chars + aconstant holdbuf-end avariable holdptr holdbuf-end holdptr a! @@ -66,34 +71,37 @@ Create main-task has? OS [IF] 100 [ELSE main-task UNLOCK tup ! LOCK -Variable udp \ user area size? -anton +Variable udp ( -- a-addr ) \ gforth +\ user area size? -anton AUser next-task main-task next-task ! AUser prev-task main-task prev-task ! AUser save-task 0 save-task ! AUser sp0 ( -- a-addr ) \ gforth -\G USER VARIABLE: Initial value of the data stack pointer. +\G @code{User} variable -- initial value of the data stack pointer. \ sp0 is used by douser:, must be user ' sp0 Alias s0 ( -- a-addr ) \ gforth \G OBSOLETE alias of @code{sp0} AUser rp0 ( -- a-addr ) \ gforth -\G USER VARIABLE: Initial value of the return stack pointer. +\G @code{User} variable -- initial value of the return stack pointer. ' rp0 Alias r0 ( -- a-addr ) \ gforth \G OBSOLETE alias of @code{rp0} AUser fp0 ( -- a-addr ) \ gforth -\G USER VARIABLE: Initial value of the floating-point stack pointer. +\G @code{User} variable -- initial value of the floating-point stack pointer. \ no f0, because this leads to unexpected results when using hex AUser lp0 ( -- a-addr ) \ gforth -\G USER VARIABLE: Initial value of the locals stack pointer. +\G @code{User} variable -- initial value of the locals stack pointer. ' lp0 Alias l0 ( -- a-addr ) \ gforth \G OBSOLETE alias of @code{lp0} AUser handler \ pointer to last throw frame +has? backtrace [IF] User backtrace-empty \ true if the next THROW should store a backtrace AUser backtrace-rp0 \ rp at last call of interpret +[THEN] \ AUser output \ AUser input @@ -104,20 +112,20 @@ AUser "error 0 "error ! [IFUNDEF] #tib \ in ec-Version we may define this ourself User tibstack \ saves >tib in execute User >tib \ pointer to terminal input buffer - User #tib ( -- a-addr ) \ core-ext - \G USER VARIABLE: @var{a-addr} is the address of a cell containing + User #tib ( -- a-addr ) \ core-ext number-t-i-b + \G @code{User} variable -- @i{a-addr} is the address of a cell containing \G the number of characters in the terminal input buffer. \G OBSOLESCENT: @code{source} superceeds the function of this word. - User >in ( -- a-addr ) \ core - \G USER VARIABLE: @var{a-addr} is the address of a cell containing the - \G char offset from the start of the terminal input buffer to the - \G start of the parse area. + User >in ( -- a-addr ) \ core to-in + \G @code{User} variable -- @i{a-addr} is the address of a cell containing the + \G char offset from the start of the input buffer to the start of the + \G parse area. 0 >in ! \ char number currently processed in tib [THEN] has? file [IF] - User blk ( -- a-addr ) \ block - \G USER VARIABLE: @var{a-addr} is the address of a cell containing zero + User blk ( -- a-addr ) \ block b-l-k + \G @code{User} variable -- @i{a-addr} is the address of a cell containing zero \G (in which case the input source is not a block and can be identified \G by @code{source-id}) or the number of the block currently being \G interpreted. A Standard program should not alter @code{blk} directly. @@ -137,24 +145,31 @@ has? file [IF] [THEN] User base ( -- a-addr ) \ core - \G USER VARIABLE: @var{a-addr} is the address of a cell that stores the + \G @code{User} variable -- @i{a-addr} is the address of a cell that stores the \G number base used by default for number conversion during input and output. A base ! - User dpl -1 dpl ! + User dpl ( -- a-addr ) \ gforth + \G @code{User} variable -- @i{a-addr} is the address of a cell that stores the + \G position of the decimal point in the most recent numeric conversion. + \G Initialised to -1. After the conversion of a number containing no + \G decimal point, @code{@ dpl} is -1. After the conversion of @code{2.} it holds + \G 0. After the conversion of 234123.9 it contains 1, and so forth. + -1 dpl ! User state ( -- a-addr ) \ core,tools-ext - \G Recommended reading: @cite{@code{State}-smartness--Why it is evil - \G and how to exorcise it}, - \G @url{http://www.complang.tuwien.ac.at/papers/ertl98.ps.gz}; short - \G version: Don't use @code{state}! @xref{Interpretation and - \G Compilation Semantics} for an alternative. USER VARIABLE: @var{a-addr} - \G is the address of a cell containing the compilation state flag. 0 - \G => interpreting, -1 => compiling. A program shall not directly - \G alter the value of @code{state}. The following Standard words - \G alter the value in @code{state}: @code{:} (colon) @code{;} - \G (semicolon) @code{abort} @code{quit} @code{:noname} @code{[} - \G (left-bracket) @code{]} (right-bracket) @code{;code} - 0 state ! + \G @code{User} variable -- @i{a-addr} is the address of a cell + \G containing the compilation state flag. 0 => interpreting, -1 => + \G compiling. A program shall not directly alter the value of + \G @code{state}. The following Standard words alter the value in + \G @code{state}: @code{:} (colon) @code{;} (semicolon) @code{abort} + \G @code{quit} @code{:noname} @code{[} (left-bracket) @code{]} + \G (right-bracket) @code{;code}. Don't use @code{state}! For an + \G alternative see @ref{Interpretation and Compilation Semantics}. + \ Recommended reading: @cite{@code{State}-smartness--Why it is evil + \ and how to exorcise it}, + \ @url{http://www.complang.tuwien.ac.at/papers/ertl98.ps.gz}; short + \ version: Don't use @code{state}! + 0 state ! AUser normal-dp \ the usual dictionary pointer AUser dpp normal-dp dpp !