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|
if not modules then modules = { } end modules ['syst-lua'] = {
version = 1.001,
comment = "companion to syst-lua.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
local load, type, tonumber = load, type, tonumber
local find, gsub = string.find, string.gsub
local concat = table.concat
local utfchar = utf.char
local S, C, P, lpegmatch, lpegtsplitat = lpeg.S, lpeg.C, lpeg.P, lpeg.match, lpeg.tsplitat
local xmath = xmath or math
local xcomplex = xcomplex or { }
----- scannext = token.scannext
local scancmdchr = token.scancmdchrexpanded
local scantoken = token.scantoken
local getcsname = token.getcsname
local cmd = tokens.commands
local letter_code = cmd.letter
local other_char_code = cmd.other_char
local spacer_code = cmd.spacer
local other_char_code = cmd.other_char
local relax_code = cmd.relax
local register_int_code = cmd.register_int
local internal_int_code = cmd.internal_int
local register_dimen_code = cmd.register_dimen
local internal_dimen_code = cmd.internal_dimen
local register_glue_code = cmd.register_glue
local internal_glue_code = cmd.internal_glue
local register_toks_code = cmd.register_toks
local internal_toks_code = cmd.internal_toks
local char_given_code = cmd.char_given
local math_given_code = cmd.math_given
local xmath_given_code = cmd.xmath_given
local some_item_code = cmd.some_item
local getdimen = tex.getdimen
local getglue = tex.getglue
local getcount = tex.getcount
local gettoks = tex.gettoks
local gettex = tex.get
local context = context
commands = commands or { }
local commands = commands
local context = context
local implement = interfaces.implement
local dimenfactors = number.dimenfactors
local ctx_protected_cs = context.protected.cs -- more efficient
local ctx_firstoftwoarguments = context.firstoftwoarguments
local ctx_secondoftwoarguments = context.secondoftwoarguments
local ctx_firstofoneargument = context.firstofoneargument
local ctx_gobbleoneargument = context.gobbleoneargument
implement { -- will be overloaded later
name = "writestatus",
arguments = "2 arguments",
actions = logs.status,
}
function commands.doifelse(b)
if b then
ctx_firstoftwoarguments()
else
ctx_secondoftwoarguments()
end
end
function commands.doifelsesomething(b)
if b and b ~= "" then
ctx_firstoftwoarguments()
else
ctx_secondoftwoarguments()
end
end
function commands.doif(b)
if b then
ctx_firstofoneargument()
else
ctx_gobbleoneargument()
end
end
function commands.doifsomething(b)
if b and b ~= "" then
ctx_firstofoneargument()
else
ctx_gobbleoneargument()
end
end
function commands.doifnot(b)
if b then
ctx_gobbleoneargument()
else
ctx_firstofoneargument()
end
end
function commands.doifnotthing(b)
if b and b ~= "" then
ctx_gobbleoneargument()
else
ctx_firstofoneargument()
end
end
commands.testcase = commands.doifelse -- obsolete
function commands.boolcase(b)
context(b and 1 or 0)
end
function commands.doifelsespaces(str)
if find(str,"^ +$") then
ctx_firstoftwoarguments()
else
ctx_secondoftwoarguments()
end
end
local pattern = lpeg.patterns.validdimen
function commands.doifelsedimenstring(str)
if lpegmatch(pattern,str) then
ctx_firstoftwoarguments()
else
ctx_secondoftwoarguments()
end
end
local p_first = C((1-P(",")-P(-1))^0)
implement {
name = "firstinset",
arguments = "string",
actions = function(str) context(lpegmatch(p_first,str or "")) end,
public = true,
}
implement {
name = "ntimes",
arguments = { "string", "integer" },
actions = { string.rep, context }
}
implement {
name = "execute",
arguments = "string",
actions = os.execute -- wrapped in sandbox
}
implement {
name = "doifelsesame",
arguments = "2 strings",
actions = function(a,b)
if a == b then
ctx_firstoftwoarguments()
else
ctx_secondoftwoarguments()
end
end
}
implement {
name = "doifsame",
arguments = "2 strings",
actions = function(a,b)
if a == b then
ctx_firstofoneargument()
else
ctx_gobbleoneargument()
end
end
}
implement {
name = "doifnotsame",
arguments = "2 strings",
actions = function(a,b)
if a == b then
ctx_gobbleoneargument()
else
ctx_firstofoneargument()
end
end
}
-- This is a bit of a joke as I never really needed floating point expressions (okay,
-- maybe only with scaling because there one can get numbers that are too large for
-- dimensions to deal with). Of course one can write a parser in \TEX\ speak but then
-- one also needs to implement a bunch of functions. It doesn't pay of so we just
-- stick to the next gimmick. It looks inefficient but performance is actually quite
-- efficient.
do
local result = { "return " }
local word = { }
local r = 1
local w = 0
local report = logs.reporter("system","expression")
local function unexpected(c)
report("unexpected token %a",c)
end
local function unexpected(c)
report("unexpected token %a",c)
end
local function expression()
local w = 0
local r = 1
while true do
local n, i = scancmdchr()
if n == letter_code then
w = w + 1 ; word[w] = utfchar(i)
else
if w > 0 then
-- we could use a metatable for all math, complex and factors
local s = concat(word,"",1,w)
local d = dimenfactors[s]
if d then
r = r + 1 ; result[r] = "*"
r = r + 1 ; result[r] = 1/d
else
if xmath[s] then
r = r + 1 ; result[r] = "xmath."
elseif xcomplex[s] then
r = r + 1 ; result[r] = "xcomplex."
end
r = r + 1 ; result[r] = s
end
w = 0
end
if n == other_char_code then
r = r + 1 ; result[r] = utfchar(i)
elseif n == spacer_code then
-- r = r + 1 ; result[r] = " "
elseif n == relax_code then
break
elseif n == register_int_code or n == internal_int_code then
r = r + 1 ; result[r] = getcount(i)
elseif n == register_dimen_code or n == internal_dimen_code then
r = r + 1 ; result[r] = getdimen(i)
elseif n == register_glue_code or n == n == register_dimen_code_glue_code then
r = r + 1 ; result[r] = getglue(i)
elseif n == register_toks_code or n == n == register_dimen_code_toks_code then
r = r + 1 ; result[r] = gettoks(i)
elseif n == char_given_code or n == math_given_code or n == xmath_given_code then
r = r + 1 ; result[r] = i
elseif n == some_item_code then
local n = getcsname(t)
if n then
local s = gettex(n)
if s then
r = r + 1 ; result[r] = s
else
unexpected(c)
end
else
unexpected(c)
end
-- elseif n == call_code then
-- local n = getcsname(t)
-- if n then
-- local s = get_macro(n)
-- if s then
-- r = r + 1 ; result[r] = s
-- else
-- unexpected(c)
-- end
-- else
-- unexpected(c)
-- end
-- elseif n == the_code or n == convert_code or n == lua_expandable_call_code then
-- put_next(t)
-- scantoken() -- expands
else
unexpected(c)
end
end
end
local code = concat(result,"",1,r)
local func = load(code)
if type(func) == "function" then
context(func())
else
report("invalid lua %a",code)
end
end
implement {
public = true,
name = "expression",
actions = expression,
}
end
do
-- This is some 20% slower than native but we only provide this for compatibility
-- reasons so we don't care that much about it. Eventually we can drop the built-in
-- method.
local channels = { }
local lastdone = { }
local findbinfile = resolvers.findbinfile
local loadbinfile = resolvers.loadbinfile
local opentexfile = resolvers.opentexfile
local scaninteger = tokens.scanners.integer
local scankeyword = tokens.scanners.keyword
local scanstring = tokens.scanners.string
local scancsname = tokens.scanners.csname
local setmacro = tokens.setters.macro
local rlncatcodes = tex.rlncatcodes
local texgetcount = tex.getcount
local bytes = string.bytes
local getcatcode = tex.getcatcode
local char, concat = string.char, table.concat
-- This uses the normal bin lookup method that we also use for other files,
-- and in principle there is no limit on the amount of files other than the
-- operating system imposes.
local t = { }
local l = 0
implement {
name = "openin",
public = true,
usage = "value",
actions = function()
local n = scaninteger()
scankeyword("=")
local s = scanstring(true)
local c = channels[n]
if c then
c:close()
end
local f = findbinfile(s,"tex")
if f then
channels[n] = opentexfile(f)
lastdone[n] = false
else
channels[n] = false
lastdone[n] = true
end
end,
}
implement {
name = "closein",
public = true,
usage = "value",
actions = function()
local n = scaninteger()
local c = channels[n]
if c then
c:close()
end
channels[n] = false
t = { }
end,
}
-- This is not the fastest routine but hardly used, occasionally for line by line
-- input in e.g. tikz which is not that fast anyway so I'll deal with it when it
-- really is a bottleneck.
local readerror = function(what,n)
tex.error(string.formatters["too many %s brace tokens in read from channel %i"](what,n))
end
interfaces.implement {
name = "read",
public = true,
usage = "value",
actions = function(prefix)
local n = scaninteger()
local c = channels[n]
if scankeyword("line") and c then
c:gotoline(scaninteger())
end
scankeyword("to")
local m = scancsname(true)
local g = 0
local s
l = 0
if c then
while true do
local s = c and c:reader()
if s then
l = l + 1
s = gsub(s," *$","")
t[l] = s
for c in bytes(s) do
local cc = getcatcode(c)
if cc == 1 then
g = g + 1
elseif cc == 2 then
g = g - 1
end
end
if g <= 0 then
break
end
else
break
end
end
if g > 0 then
readerror("left",n)
s = ""
elseif g < 0 then
readerror("right",n)
s = ""
elseif l == 0 then
if c:endoffile() then
lastdone[n] = true
s = "\\par"
else
s = ""
end
channels[n] = false
else
local e = texgetcount("endlinechar") -- we can have tex.endline if needed
if e < 0 or e > 127 then
e = ""
else
e = " "
l = l + 1
t[l] = ""
end
s = concat(t, e, 1, l)
end
else
s = ""
end
setmacro(m, s, prefix) -- checks for frozen
end,
}
-- This is an etex extension. All characters become catcode 12 but a space gets code
-- 10. The etex manual specifies a lineending of catcode 12 too. Should we strip spaces
-- at the end? A bit weird command that we never use anyway.
implement {
name = "readline",
public = true,
usage = "value",
actions = function(prefix)
local n = scaninteger()
local c = channels[n]
if scankeyword("line") and c then
c:gotoline(scaninteger())
end
scankeyword("to")
local m = scancsname(true)
local s = c and c:reader()
if s then
local e = texgetcount("endlinechar") -- we can have tex.endline if needed
if e > 0 then -- forget about 0
s = s .. char(e)
end
else
channels[n] = false
s = ""
end
setmacro(rlncatcodes, m, s, prefix) -- checks for frozen
end,
}
-- This one uses the special lua condition option which is kind of experimental
-- but seems to work fine.
local boolean_value = tokens.values.boolean
implement {
name = "ifeof",
public = true,
usage = "condition",
actions = function()
local n = scaninteger()
return boolean_value, not channels[n]
end,
}
-- This one doesn't belong here and it might become a real primitive if we need it
-- frequently. So, for the moment we keep it in this file.
local getnest = tex.getnest
implement {
name = "ifmvl",
public = true,
usage = "condition",
actions = function()
return boolean_value, getnest("ptr") == 0
end,
}
end
|