asCScriptNode *asCParser::ParseStatement()
{
sToken t1;
GetToken(&t1);
RewindTo(&t1);
if( t1.type == ttIf )
return ParseIf();
else if( t1.type == ttFor )
return ParseFor();
else if( t1.type == ttWhile )
return ParseWhile();
else if( t1.type == ttReturn )
return ParseReturn();
else if( t1.type == ttStartStatementBlock )
return ParseStatementBlock();
else if( t1.type == ttBreak )
return ParseBreak();
else if( t1.type == ttContinue )
return ParseContinue();
else if( t1.type == ttDo )
return ParseDoWhile();
else if( t1.type == ttSwitch )
return ParseSwitch();
else
return ParseExpressionStatement();
}
/// primary
/// ::= identifierexpr
/// ::= numberexpr
/// ::= parenexpr
std::unique_ptr<ExprAST> UDFParser::ParsePrimary() {
switch (cur_tok_) {
default:
return LogError("unknown token when expecting an expression");
case tok_identifier:
return ParseIdentifierExpr();
case tok_number:
return ParseNumberExpr();
case '(':
return ParseParenExpr();
case tok_return:
return ParseReturn();
case tok_if:
return ParseIfExpr();
case tok_semicolon:
return nullptr;
}
}
AST* ParseOperator(ParserState* parser) {
AST* ast;
switch(parser->currentToken.type) {
case TOKEN_BEGIN:
return ParseBlock(parser);
case TOKEN_ID:
ast = parser->nextToken.type == TOKEN_LEFTBRACKET ? ParseFunctionCall(parser) : ParseAssignment(parser);
Match(parser, TOKEN_SEMICOLON);
return ast;
case TOKEN_LOCAL:
ast = ParseAssignment(parser);
Match(parser, TOKEN_SEMICOLON);
return ast;
case TOKEN_WHILE:
return ParseWhileCycle(parser);
case TOKEN_IF:
return ParseIfStatement(parser);
case TOKEN_FUNCTION:
return ParseFunctionDefinition(parser);
case TOKEN_RETURN:
ast = ParseReturn(parser);
Match(parser, TOKEN_SEMICOLON);
return ast;
case TOKEN_PRINT:
ast = ParsePrint(parser);
Match(parser, TOKEN_SEMICOLON);
return ast;
case TOKEN_INCLUDE:
return ParseInclude(parser);
case TOKEN_LOAD:
ast = ParseLoad(parser);
Match(parser, TOKEN_SEMICOLON);
return ast; /** TODO: Factor common parts out of switch */
}
FailWithUnexpectedToken(parser, parser->currentToken.type, TOKEN_ID);
return NULL;
}
static void ParseStatement (scontext_t owner)
{
if (StatementIndex == MAX_STATEMENT_DEPTH)
{
PR_ParseError("statement overflow");
}
ContextHistory[StatementIndex++] = owner;
if (TK_CHECK(TK_LBRACE))
{
ContextLevel += EnterContext[owner];
do
{
ParseStatement(owner);
} while (!TK_CHECK(TK_RBRACE));
ContextLevel -= EnterContext[owner];
StatementIndex--;
return;
}
if (TK_CHECK(TK_SEMICOLON))
{
StatementIndex--;
return;
}
if (LX_CheckFetch("return"))
{
ParseReturn();
StatementIndex--;
return;
}
if (LX_CheckFetch("loop"))
{
ParseLoop();
StatementIndex--;
return;
}
if (LX_CheckFetch("while"))
{
ParseWhile();
StatementIndex--;
return;
}
if (LX_CheckFetch("until"))
{
ParseUntil();
StatementIndex--;
return;
}
if (LX_CheckFetch("do"))
{
ParseDo();
StatementIndex--;
return;
}
if (LX_CheckFetch("switch"))
{
ParseSwitch();
StatementIndex--;
return;
}
if (LX_CheckFetch("case"))
{
if (owner != SCONTEXT_SWITCH)
{
PR_ParseError("misplaced case");
}
ParseCase();
StatementIndex--;
return;
}
if (LX_CheckFetch("break"))
{
if (BreakAncestor() == false)
{
PR_ParseError("misplaced break");
}
ParseBreak();
StatementIndex--;
return;
}
if (LX_CheckFetch("continue"))
{
if (ContinueAncestor() == false)
{
PR_ParseError("misplaced continue");
}
ParseContinue();
StatementIndex--;
return;
}
if (LX_CheckFetch("default"))
{
ParseDefault();
StatementIndex--;
return;
}
if (LX_CheckFetch("thinktime"))
{
ParseThinktime();
StatementIndex--;
return;
}
if (LX_CheckFetch("local"))
{
ParseLocalDefs();
StatementIndex--;
return;
}
if (LX_Check("float") || LX_Check("vector")
|| LX_Check("entity") || LX_Check("string")
|| LX_Check("void"))
{
ParseLocalDefs();
StatementIndex--;
return;
}
if (LX_CheckFetch("if"))
{
ParseIf();
StatementIndex--;
return;
}
EX_Expression(TOP_PRIORITY);
LX_Require(";");
StatementIndex--;
}
/* ParseStatement - parse a statement */
void ParseStatement(ParseContext *c, Token tkn)
{
/* dispatch on the statement keyword */
switch (tkn) {
case T_REM:
/* just a comment so ignore the rest of the line */
break;
case T_DEF:
ParseDef(c);
break;
case T_END_DEF:
ParseEndDef(c);
break;
case T_DIM:
ParseDim(c);
break;
case T_LET:
ParseLet(c);
break;
case T_IF:
ParseIf(c);
break;
case T_ELSE:
ParseElse(c);
break;
case T_ELSE_IF:
ParseElseIf(c);
break;
case T_END_IF:
ParseEndIf(c);
break;
case T_END:
ParseEnd(c);
break;
case T_FOR:
ParseFor(c);
break;
case T_NEXT:
ParseNext(c);
break;
case T_DO:
ParseDo(c);
break;
case T_DO_WHILE:
ParseDoWhile(c);
break;
case T_DO_UNTIL:
ParseDoUntil(c);
break;
case T_LOOP:
ParseLoop(c);
break;
case T_LOOP_WHILE:
ParseLoopWhile(c);
break;
case T_LOOP_UNTIL:
ParseLoopUntil(c);
break;
case T_STOP:
ParseStop(c);
break;
case T_GOTO:
ParseGoto(c);
break;
case T_RETURN:
ParseReturn(c);
break;
case T_PRINT:
ParsePrint(c);
break;
case T_IDENTIFIER:
if (SkipSpaces(c) == ':') {
DefineLabel(c, c->token, codeaddr(c));
break;
}
UngetC(c);
default:
SaveToken(c, tkn);
ParseImpliedLetOrFunctionCall(c);
break;
}
}
