语法解析

1 files changed, 311 insertions, 0 deletions

diff --git a/src/parser/grammar.lua b/src/parser/grammar.lua
new file mode 100644
index 00000000..eedbd8da
--- /dev/null
+++ b/src/parser/grammar.lua
@@ -0,0 +1,311 @@
+local re = require 'parser.relabel'
+local m = require 'lpeglabel'
+local calcline = require 'parser.calcline'
+
+local scriptBuf = ''
+local compiled = {}
+local parser
+
+local defs = setmetatable({}, {__index = function (self, key)
+    self[key] = function (...)
+        if parser[key] then
+            return parser[key](...)
+        end
+    end
+    return self[key]
+end})
+
+defs.nl = (m.P'\r\n' + m.S'\r\n') / function ()
+    if parser.nl then
+        return parser.nl()
+    end
+end
+defs.s  = m.S' \t'
+defs.S  = - defs.s
+defs.ea = '\a'
+defs.eb = '\b'
+defs.ef = '\f'
+defs.en = '\n'
+defs.er = '\r'
+defs.et = '\t'
+defs.ev = '\v'
+local eof = re.compile '!. / %{SYNTAX_ERROR}'
+
+local function grammar(tag)
+    return function (script)
+        scriptBuf = script .. '\r\n' .. scriptBuf
+        compiled[tag] = re.compile(scriptBuf, defs) * eof
+    end
+end
+
+local labels = {
+
+}
+
+local function errorpos(lua, pos, err)
+    local row, col = calcline.rowcol(lua, pos)
+    local str = calcline.line(lua, row)
+    return {
+        lua = lua,
+        line = row,
+        pos = col,
+        err = err,
+        code = str,
+        level = 'error',
+    }
+end
+
+grammar 'Comment' [[
+Comment         <-  '--' (LongComment / ShortComment)
+LongComment     <-  '[' {:eq: '='* :} '[' CommentClose
+CommentClose    <-  ']' =eq ']' / . CommentClose
+ShortComment    <-  (!%nl .)*
+]]
+
+grammar 'Sp' [[
+Sp  <-  (Comment / %nl / %s)*
+]]
+
+grammar 'Common' [[
+Cut         <-  ![a-zA-Z0-9_]
+X16         <-  [a-fA-F0-9]
+
+AND         <-  Sp 'and'      Cut
+BREAK       <-  Sp 'break'    Cut
+DO          <-  Sp 'do'       Cut
+ELSE        <-  Sp 'else'     Cut
+ELSEIF      <-  Sp 'elseif'   Cut
+END         <-  Sp 'end'      Cut
+FALSE       <-  Sp 'false'    Cut
+FOR         <-  Sp 'for'      Cut
+FUNCTION    <-  Sp 'function' Cut
+GOTO        <-  Sp 'goto'     Cut
+IF          <-  Sp 'if'       Cut
+IN          <-  Sp 'in'       Cut
+LOCAL       <-  Sp 'local'    Cut
+NIL         <-  Sp 'nil'      Cut
+NOT         <-  Sp 'not'      Cut
+OR          <-  Sp 'or'       Cut
+REPEAT      <-  Sp 'repeat'   Cut
+RETURN      <-  Sp 'return'   Cut
+THEN        <-  Sp 'then'     Cut
+TRUE        <-  Sp 'true'     Cut
+UNTIL       <-  Sp 'until'    Cut
+WHILE       <-  Sp 'while'    Cut
+
+Esc         <-  '\' EChar
+EChar       <-  'a' -> ea
+            /   'b' -> eb
+            /   'f' -> ef
+            /   'n' -> en
+            /   'r' -> er
+            /   't' -> et
+            /   'v' -> ev
+            /   '\'
+            /   '"'
+            /   "'"
+            /   %nl
+            /   'z' (%nl / %s)* -> ''
+            /   'x' X16 X16
+            /   [0-9] [0-9]? [0-9]?
+            /   'u{' X16^+1^-6 '}'
+
+Comp        <-  Sp CompList
+CompList    <-  '<='
+            /   '>='
+            /   '<'
+            /   '>'
+            /   '~='
+            /   '=='
+BOR         <-  Sp '|'
+BXOR        <-  Sp '~'
+BAND        <-  Sp '&'
+Bshift      <-  Sp BshiftList
+BshiftList  <-  '<<'
+            /   '>>'
+Concat      <-  Sp '..'
+Adds        <-  Sp AddsList
+AddsList    <-  '+'
+            /   '-'
+Muls        <-  Sp MulsList
+MulsList    <-  '*'
+            /   '//'
+            /   '/'
+            /   '%'
+Unary       <-  Sp UnaryList
+UnaryList   <-  'not'
+            /   '#'
+            /   '-'
+            /   '~'
+POWER       <-  Sp '^'
+
+PL          <-  Sp '('
+PR          <-  Sp ')'
+BL          <-  Sp '['
+BR          <-  Sp ']'
+TL          <-  Sp '{'
+TR          <-  Sp '}'
+COMMA       <-  Sp ','
+SEMICOLON   <-  Sp ';'
+DOTS        <-  Sp '...'
+DOT         <-  Sp '.'
+COLON       <-  Sp ':'
+LABEL       <-  Sp '::'
+ASSIGN      <-  Sp '='
+]]
+
+grammar 'Nil' [[
+Nil         <-  NIL
+]]
+
+grammar 'Boolean' [[
+Boolean     <-  TRUE
+            /   FALSE
+]]
+
+grammar 'String' [[
+String      <-  Sp StringDef
+StringDef   <-  '"' (Esc / !%nl !'"' .)* '"'
+            /   "'" (Esc / !%nl !"'" .)* "'"
+            /   '[' {:eq: '='* :} '[' StringClose
+StringClose <-  ']' =eq ']' / . StringClose
+]]
+
+grammar 'Number' [[
+Number      <-  Sp NumberDef
+NumberDef   <-  Number16 / Number10
+
+Number10    <-  Integer10 Float10
+Integer10   <-  '0' / [1-9] [0-9]*
+Float10     <-  ('.' [0-9]*)? ([eE] [+-]? [1-9]? [0-9]*)?
+
+Number16    <-  Integer16 Float16
+Integer16   <-  '0' [xX] X16*
+Float16     <-  ('.' X16*)? ([pP] [+-]? [1-9]? [0-9]*)?
+]]
+
+grammar 'Name' [[
+Name        <-  Sp [a-zA-Z_] [a-zA-Z0-9_]*
+]]
+
+grammar 'Exp' [[
+Exp         <-  ExpOr
+ExpOr       <-  ExpAnd     (OR     ExpAnd)*
+ExpAnd      <-  ExpCompare (AND    ExpCompare)*
+ExpCompare  <-  ExpBor     (Comp   ExpBor)*
+ExpBor      <-  ExpBxor    (BOR    ExpBxor)*
+ExpBxor     <-  ExpBand    (BXOR   ExpBand)*
+ExpBand     <-  ExpBshift  (BAND   ExpBshift)*
+ExpBshift   <-  ExpConcat  (Bshift ExpConcat)*
+ExpConcat   <-  ExpAdds    (Concat ExpAdds)*
+ExpAdds     <-  ExpMuls    (Adds   ExpMuls)*
+ExpMuls     <-  ExpUnary   (Muls   ExpUnary)*
+ExpUnary    <-             (Unary  ExpPower)
+            /                      ExpPower
+ExpPower    <-  ExpUnit    (POWER  ExpUnit)*
+ExpUnit     <-  Nil
+            /   Boolean
+            /   String
+            /   Number
+            /   DOTS
+            /   Table
+            /   Function
+            /   Simple
+
+Simple      <-  Prefix (Suffix)*
+Prefix      <-  PL Exp PR
+            /   Name
+Suffix      <-  DOT Name
+            /   COLON Name
+            /   Table
+            /   String
+            /   BL Exp BR
+            /   PL ArgList? PR
+
+ArgList     <-  Arg (COMMA Arg)*
+Arg         <-  DOTS
+            /   Exp
+
+Table       <-  TL TableFields? TR
+TableFields <-  TableField (TableSep TableField)* TableSep?
+TableSep    <-  COMMA / SEMICOLON
+TableField  <-  NewIndex / NewField / Exp
+NewIndex    <-  BL Exp BR ASSIGN Exp
+NewField    <-  Name ASSIGN Exp
+
+Function    <-  FUNCTION PL ArgList? PR
+                    (!END Action)*
+                END
+
+-- 纯占位，修改了 `relabel.lua` 使重复定义不抛错
+Action      <-  !. .
+]]
+
+grammar 'Action' [[
+Action      <-  SEMICOLON / Do / Break / Return / Label / GoTo / If / For / While / Repeat / Set / Call
+
+ExpList     <-  Exp (COMMA Exp)*
+
+Do          <-  DO (!END Action)* END
+
+Break       <-  BREAK
+
+Return      <-  RETURN ExpList?
+
+Label       <-  LABEL Name LABEL
+
+GoTo        <-  GOTO Name
+
+If          <-  IfPart
+                ElseIfPart*
+                ElsePart?
+                END
+IfPart      <-  IF Exp THEN
+                    (!ELSEIF !ELSE !END Action)*
+ElseIfPart  <-  ELSEIF Exp THEN
+                    (!ELSE !END Action)*
+ElsePart    <-  ELSE
+                    (!END Action)*
+
+For         <-  Loop / In
+Loop        <-  FOR LoopStart LoopFinish LoopStep? DO
+                    (!END Action)*
+                END
+LoopStart   <-  Name ASSIGN Exp
+LoopFinish  <-  COMMA Exp
+LoopStep    <-  COMMA Exp
+
+In          <-  FOR NameList IN ExpList DO
+                    (!END Action)*
+                END
+NameList    <-  Name (COMMA Name)*
+
+While       <-  WHILE Exp DO
+                    (!END Action)*
+                END
+
+Repeat      <-  REPEAT
+                    (!UNTIL Action)*
+                UNTIL Exp
+
+Set         <-  LOCAL Name ASSIGN Exp
+            /   Simple     ASSIGN Exp
+
+Call        <-  Prefix (Suffix)*
+]]
+
+grammar 'Lua' [[
+Lua         <-  (Sp Action)* Sp
+]]
+
+return function (lua, mode, parser_)
+    parser = parser_ or {}
+    mode = mode or 'lua'
+    local r, e, pos = compiled[mode]:match(lua)
+    if not r then
+        local err = errorpos(lua, pos, e)
+        return nil, err
+    end
+
+    return r
+end