Fsyntax is ready (...but messing with syntax sucks! :)

[Asko Kauppi <askok@...>]

I got the syntax-aware filtering done, and as a sample below is the  
code required to have "do ... end" be paranthesless function parameters.

So far, so good.

Selftests run, as long as a script don't have "for i=1,h do .." or  
similar while constructs. :))  Sad. Funny.

The point is, there is now a slimmer (?) alternative for MetaLua, but  
messing with existing syntax is sure to have surprising concequences,  
all of which are not immediately obvious. Roberto et.al. have known  
this all the time, of course... Good for them.

http://kotisivu.dnainternet.fi/askok/bin/Filters-061206.zip

-rw-r--r--    1 asko  staff    550 Dec  6 00:22 Makefile
-rw-r--r--    1 asko  staff   5060 Dec  6 00:40 fdoend.lua
-rw-r--r--    1 asko  staff  12510 Dec  5 23:52 fluax.lua
-rw-r--r--    1 asko  staff  19283 Dec  6 00:23 fsyntax.lua
-rw-r--r--    1 asko  staff  13664 Dec  6 00:09 ftools.lua
-rw-r--r--    1 asko  staff    661 Dec  5 23:53 test-fdoend.lua

Please download it.

usage:	make
	make speed

requires:
	Lua 5.1 with token filter patch applied

If this was added with a tokenizer, and code generator, it could be  
any syntax engine. I have no interest to go further that road. But  
someone might? :)

-asko

-----
-- FDOEND.LUA
--
-- exp do .. end  -->  exp ( function() .. end )
--
-- usage: lua -lftools -lfsyntax -lfdoend ...
--
local alt= 	assert( FILTER.syntax.alt )
local altN_but_last= assert( FILTER.syntax.altN_but_last )
local opt= 	assert( FILTER.syntax.opt )
local args= 	assert( FILTER.syntax.args )
local block= 	assert( FILTER.syntax.block )
local exp= 	assert( FILTER.syntax.exp )
local explist1= assert( FILTER.syntax.explist1 )
local fieldlist= assert( FILTER.syntax.fieldlist )
local funcbody= assert( FILTER.syntax.funcbody )
local var= 	assert( FILTER.syntax.var )

local function CATCH( p, first )
    p:replace( first-1, 1, "(", "function", "(", ")" )  -- beginning
    p:replace( 0, 0, ")" )  -- after
end

local function CATCH2( p, first )
    p:replace( first-1, 0, "(" )  -- beginning
    p:replace( 0, 0, ")" )  -- after
end

FILTER.syntax.link{
    ["functioncall"]= { -- prefixexp
                        alt{ ['(']= {exp,')'},
                             ["<name>"]=true },
                        altN_but_last{ ['[']= {exp,']'},
                                       ['.']= "<name>",
                                       ["do"]= { block, "end",  
convert=CATCH },
                                       ["function"]= { funcbody,  
convert=CATCH2 },
                                       [':']= {"<name>",args},
                                       args },
                        -- end of prefixexp
                        opt{':',"<name>"},
                        args
                      },

    ["args"]=   alt{ ['(']= { opt(explist1), ')' },
                     ["<string>"]= true,
                     ['{']= {opt(fieldlist),'}'},
                     ["do"]= { block, "end", convert=CATCH },
                     ["function"]= { funcbody, convert=CATCH2 },
                   },
    }