public ImportStmt(BasicLit src, TokenPos pos)
{
Source = src;
ImportPos = pos;
BuildRelation();
}
List <ImportStmt> ParseImportStmt( )
{
var importList = new List <ImportStmt>();
while (CurrTokenType == TokenType.Import &&
CurrTokenType != TokenType.EOF)
{
var defpos = CurrTokenPos;
Expect(TokenType.Import);
var tk = Expect(TokenType.QuotedString);
var pkgName = new BasicLit(tk.Value, (TokenType)tk.MatcherID, tk.Pos);
var n = new ImportStmt(pkgName, defpos);
importList.Add(n);
ScopeManager.Declare(n, ScopeMgr.PackageScope, tk.Value, defpos, SymbolUsage.Package);
// 如果包存在, 就不会在定义
var pkg = Exe.GetPackageByName(tk.Value);
if (pkg == null)
{
Compiler.Import(_exe, _loader, tk.Value, tk.Value, ImportMode.Directory);
}
}
return(importList);
}
BasicLit ParseBasicLit()
{
switch (CurrTokenType)
{
case TokenType.Number:
case TokenType.QuotedString:
{
var x = new BasicLit(_token.Value, CurrTokenType, CurrTokenPos);
Next();
return(x);
}
}
throw new CompileException("Expect Literal value", CurrTokenPos);
}
Expr ParseOperand(bool lhs)
{
var defPos = CurrTokenPos;
switch (CurrTokenType)
{
case TokenType.Identifier: // a = b
{
var x = ParseIdent();
ScopeMgr.Resolve(x);
return(x);
}
case TokenType.Base: // a= base.foo()
{
Next();
return(new BaseLit(defPos));
}
case TokenType.Number:
case TokenType.QuotedString:
{
var x = new BasicLit(_token.Value, CurrTokenType, CurrTokenPos);
Next();
return(x);
}
case TokenType.LParen: // () 括号表达式
{
Next();
var x = ParseExpr(false);
var rparenPos = CurrTokenPos;
Expect(TokenType.RParen);
return(new ParenExpr(x, defPos, rparenPos));
}
case TokenType.LBracket: // a = [] 数组初始化
{
Next();
List <Expr> values = new List <Expr>();
while (CurrTokenType != TokenType.RBracket &&
CurrTokenType != TokenType.EOF)
{
values.Add(ParseOperand(false));
if (CurrTokenType == TokenType.RBracket ||
CurrTokenType == TokenType.EOF)
{
break;
}
Expect(TokenType.Comma);
}
var rPos = CurrTokenPos;
Expect(TokenType.RBracket);
return(new ArrayExpr(values, defPos, rPos));
}
case TokenType.LBrace: // a = {} Map初始化
{
Next();
Dictionary <BasicLit, Expr> mapValues = new Dictionary <BasicLit, Expr>();
while (CurrTokenType != TokenType.RBrace &&
CurrTokenType != TokenType.EOF)
{
var key = ParseBasicLit();
Expect(TokenType.Colon);
var value = ParseRHS();
mapValues.Add(key, value);
if (CurrTokenType == TokenType.RBrace ||
CurrTokenType == TokenType.EOF)
{
break;
}
Expect(TokenType.Comma);
}
var rPos = CurrTokenPos;
Expect(TokenType.RBrace);
return(new MapExpr(mapValues, defPos, rPos));
}
case TokenType.Func: // a = func( ) {}
{
Next();
var scope = ScopeMgr.OpenScope(ScopeType.Closure, defPos);
var paramlist = ParseParameters(scope, false);
var body = ParseBody(scope);
var funclit = new FuncLit(body, new FuncType(defPos, paramlist, scope));
return(funclit);
}
}
throw new CompileException("Unknown operand", CurrTokenPos);
}
