From ba0970cedef4e5ab71e6ca29ecd062dd0708bf35 Mon Sep 17 00:00:00 2001 From: helixhorned Date: Sun, 3 Mar 2013 16:06:12 +0000 Subject: [PATCH] Lunatic translator: dangling else for the 1000th time: not dangling any more. Also update test/dangling_else.con. See there for how if* cascades are handled in CON. It's actually kind of pretty. Also, take care to handle code deferred to after the if/if-else properly (ifpdistl, ifpdistg, ifcanseetartet). git-svn-id: https://svn.eduke32.com/eduke32@3534 1a8010ca-5511-0410-912e-c29ae57300e0 --- polymer/eduke32/source/lunatic/lunacon.lua | 130 ++++++++---------- .../source/lunatic/test/dangling_else.con | 64 +++++++-- 2 files changed, 117 insertions(+), 77 deletions(-) diff --git a/polymer/eduke32/source/lunatic/lunacon.lua b/polymer/eduke32/source/lunatic/lunacon.lua index 92f688dfa..75f58d3e3 100644 --- a/polymer/eduke32/source/lunatic/lunacon.lua +++ b/polymer/eduke32/source/lunatic/lunacon.lua @@ -54,7 +54,7 @@ lpeg.setmaxstack(1024); local Pat, Set, Range, Var = lpeg.P, lpeg.S, lpeg.R, lpeg.V -local POS = lpeg.Cp +local POS, Cc, Ctab = lpeg.Cp, lpeg.Cc, lpeg.Ct -- CON language definitions (among other things, all keywords pattern). local conl = require("con_lang") @@ -1597,9 +1597,9 @@ local handle = -- readgamevar or savegamevar RSgamevar = function(identifier, dosave) -- check identifier for sanity - if (not identifier:match("^[A-Za-z][A-Za-z0-9_]*$")) then - errprintf("%s: invalid identifier name `%s' for config file persistence", - g_lastkw) + if (not identifier:match("^[A-Za-z][A-Za-z0-9_%-]*$")) then + errprintf("%s: bad identifier `%s' for config file persistence", + g_lastkw, identifier) return "_BADRSGV()" end @@ -2207,10 +2207,10 @@ local Cif = { ifrnd = cmd(D) / "_con.rnd(%1)", - ifpdistl = cmd(D) - / function(val) return "_dist<"..val, "", "_con._sleepcheck(_aci,_dist)" end, - ifpdistg = cmd(D) - / function(val) return "_dist>"..val, "", "_con._sleepcheck(_aci,_dist)" end, + ifpdistl = cmd(D) -- DEFER + / function(val) return { "_dist<"..val, nil, "_con._sleepcheck(_aci,_dist)" } end, + ifpdistg = cmd(D) -- DEFER + / function(val) return { "_dist>"..val, nil, "_con._sleepcheck(_aci,_dist)" } end, ifactioncount = cmd(D) / ACS":get_acount()>=%1", ifcount = cmd(D) @@ -2315,8 +2315,10 @@ local Cif = { / "false", -- TODO_MP ifcanshoottarget = cmd() / "_con._canshoottarget(_dist,_aci)", - ifcanseetarget = cmd() -- XXX: 1536 is SLEEPTIME - / function() return format("_con._canseetarget(%s,%s)", SPS"", PLS""), ACS".timetosleep=1536" end, + ifcanseetarget = cmd() -- DEFER -- XXX: 1536 is SLEEPTIME + / function() + return { format("_con._canseetarget(%s,%s)", SPS"", PLS""), ACS".timetosleep=1536" } + end, ifcansee = cmd() * #sp1 / format("_con._cansee(_aci,%s)", PLS""), ifbulletnear = cmd() @@ -2467,7 +2469,7 @@ local function after_cmd_Cmt(subj, pos, ...) return true -- don't return any captures end --- attach the command names at the front! +-- Attach the command names at the front! local function attachnames(kwtab, matchtimefunc) for cmdname,cmdpat in pairs(kwtab) do -- The match-time function capture at the end is so that every command @@ -2598,55 +2600,56 @@ local t_good_identifier = Range("AZ", "az", "__") * Range("AZ", "az", "__", "09" local t_broken_identifier = BadIdent(-((tok.number + t_good_identifier) * (sp1 + Set("[]:"))) * (alphanum + Set(BAD_ID_CHARS0)) * (alphanum + Set(BAD_ID_CHARS1))^0) --- These two tables hold code to be inserted at a later point: either at --- the end of the "if" body, or the end of the whole "if [else]" block. --- For CON interpreter patterns like these: --- VM_CONDITIONAL(); --- --- (Still not the same if the body returns or jumps out) -local g_endIfCode = {} -local g_endIfElseCode = {} +function on.if_else_end(ifconds, ifstmt, elsestmt, ...) + assert(#{...}==0) + assert(type(ifconds)=="table" and #ifconds>=1) -local function add_deferred_code(tab, lev, str) - if (str ~= nil) then - assert(type(str)=="string") - tab[lev] = str - end -end + -- A condition may be a table carrying "deferred" code to add either + -- [1] after the 'if' or + -- [2] after the whole if/else block. + -- In CON, it's always the same code for the same kind of "deferedness", + -- and it's always idempotent (executing it multiple times has the same + -- effect as executing it once), so generate code for it only once, too. + local deferred = { nil, nil } -local function get_deferred_code(tab, lev, code) - if (tab[lev]) then - code = code..tab[lev] - tab[lev] = nil + local ifcondstr = {} + for i=1,#ifconds do + local cond = ifconds[i] + local hasmore = type(cond=="table") + + ifcondstr[i] = hasmore and cond[1] or cond + assert(type(ifcondstr[i])=="string") + + if (hasmore) then + for i=1,2 do + if (deferred[i]==nil) then + deferred[i] = cond[i+1] + end + end + end end + + -- Construct a string of ANDed conditions + local conds = "(" .. table.concat(ifcondstr, ")and(") .. ")" + + local code = { + format("if %s then", conds), + ifstmt, + } + + code[#code+1] = deferred[1] + + if (elsestmt~=nil) then + code[#code+1] = "else" + code[#code+1] = elsestmt + end + + code[#code+1] = "end" + code[#code+1] = deferred[2] + return code end -function on.if_begin(condstr, endifstr, endifelsestr) - assert(type(condstr)=="string") - - add_deferred_code(g_endIfCode, g_iflevel, endifstr) - add_deferred_code(g_endIfElseCode, g_ifelselevel, endifelsestr) - - g_iflevel = g_iflevel+1 - g_ifelselevel = g_ifelselevel+1 - - return format("if (%s) then", condstr) -end - -function on.if_end() - g_iflevel = g_iflevel-1 - local code = get_deferred_code(g_endIfCode, g_iflevel, "") - if (code ~= "") then - return code - end -end - -function on.if_else_end() - g_ifelselevel = g_ifelselevel-1 - return get_deferred_code(g_endIfElseCode, g_ifelselevel, "end ") -end - function on.while_begin(v1, v2) table.insert(g_isWhile, true) return format("while (%s~=%s) do", v1, v2) @@ -2788,18 +2791,8 @@ local Grammar = Pat{ default_block = lpeg.Ct(sp1 * Keyw("default") * (sp0*":"*sp0 + sp1) * stmt_list_nosp_or_eps), -- * "break", - optional_else = (sp1 * lpeg.C("else") * sp1 * Var("single_stmt"))^-1, - - if_else_bodies = Var("single_stmt2") * (Pat("")/on.if_end) * Var("optional_else"), - - if_stmt = con_if_begs/on.if_begin * sp1 - * Var("if_else_bodies") - * (Pat("")/on.if_else_end), - - if_stmt2 = con_if_begs/on.if_begin * sp1 - * (-con_if_begs * Var("single_stmt") * (Pat("")/on.if_end) - + Var("if_else_bodies")) - * (Pat("")/on.if_else_end), + if_stmt = lpeg.Ct((con_if_begs * sp1)^1) * Var("single_stmt") + * (sp1 * Keyw("else") * sp1 * Var("single_stmt"))^-1 / on.if_else_end, while_stmt = Keyw("whilevarvarn") * sp1 * tok.rvar * sp1 * tok.rvar / on.while_begin * sp1 * Var("single_stmt") * (lpeg.Cc(nil) / on.while_end) @@ -2807,11 +2800,10 @@ local Grammar = Pat{ * sp1 * Var("single_stmt") * (lpeg.Cc(nil) / on.while_end), stmt_common = Keyw("{") * sp1 * "}" -- space separation of commands in CON is for a reason! - + Keyw("{") * sp1 * stmt_list * sp1 * "}" - + con_inner_command + Var("switch_stmt") + Var("while_stmt"), + + Keyw("{") * sp1 * lpeg.Ct(stmt_list) * sp1 * "}" + + con_inner_command + Var("switch_stmt") + lpeg.Ct(Var("while_stmt")), single_stmt = Stmt( lone_else^-1 * (Var("stmt_common") + Var("if_stmt")) ), - single_stmt2 = Stmt( lone_else^-1 * (Var("stmt_common") + Var("if_stmt2")) ), -- a non-empty statement/command list stmt_list = Var("single_stmt") * (sp1 * Var("single_stmt"))^0, diff --git a/polymer/eduke32/source/lunatic/test/dangling_else.con b/polymer/eduke32/source/lunatic/test/dangling_else.con index ffb4415de..70cf9a710 100644 --- a/polymer/eduke32/source/lunatic/test/dangling_else.con +++ b/polymer/eduke32/source/lunatic/test/dangling_else.con @@ -1,10 +1,58 @@ -// a dangling 'else' in CON attaches to the outermost matching 'if' -onevent EVENT_INIT - redefinequote 114 DANGLING ELSE CHECK FAILED 1 - ifvare 0 1 - ifvare 0 0 redefinequote 114 DANGLING ELSE CHECK FAILED 2 - else - redefinequote 114 DANGLING ELSE CHECK PASSED +// In CON, the dangling else ambiguity is resolved in a very peculiar way: +// A cascade "ifP1 ifP2 ifP3 Stmt1 ... else Stmt2" is considered as if the +// predicates P1, P2, P3, ... are combined with a logical AND. +// So effectively, there is no ambiguity at all, and one of Stmt1 and Stmt2 +// is guaranteed to be taken. - echo 114 +define Q 114 +define GLOBAL 0 + +gamevar x 0 GLOBAL +// divisible by 2, 3, 5? +gamevar xm2 0 GLOBAL +gamevar xm3 0 GLOBAL +gamevar xm5 0 GLOBAL + +state testelse + setvarvar xm2 x, modvar xm2 2 + setvarvar xm3 x, modvar xm3 3 + setvarvar xm5 x, modvar xm5 5 + + redefinequote Q ERROR: one path of if/else must be taken + + ifvarn xm2 0 + ifvarn xm3 0 + ifvarn xm5 0 + redefinequote Q x=%d is not divisible by either 2, 3 or 5 + else + redefinequote Q x=%d is divisible by either 2, 3 or 5 + + qsprintf Q Q x + userquote Q +ends + +onevent EVENT_ENTERLEVEL + setvar x 0 + whilevarn x 31 + { + state testelse + addvar x 1 + } +endevent + +// Test deferred code. This CON code doesn't make much sense, but check out +// the generated Lua code... +onevent EVENT_JUMP + ifpdistl 100 ifpdistg 0 ifcanseetarget + { + palfrom 32 32 32 + ifcanseetarget + quote 29 + ifcanseetarget + quote 30 + setvar x 0 + state testelse + } + else ifcanseetarget + quote 31 endevent