ExpPtr parseCall (Lexer& lex, ExpPtr in)
{
auto args = parseTuple(lex);
ExpList exps;
exps.reserve(args->subexps.size() + 1);
exps.push_back(in);
exps.insert(exps.end(), args->subexps.begin(), args->subexps.end());
return Exp::make(eCall, exps, in->span + args->span);
}
void parseBlockExp (Lexer& lex, ExpList& list)
{
switch (lex.current().tok)
{
case tSemicolon:
lex.advance();
break;
case tLet:
list.push_back(parseLet(lex));
lex.eat(tSemicolon);
break;
case tLCurl:
list.push_back(parseBlock(lex));
break;
case tIf:
list.push_back(parseCond(lex));
break;
case tLoop:
list.push_back(parseLoop(lex));
break;
case tFor:
list.push_back(parseFor(lex));
break;
// everthing else does
default:
list.push_back(parseAssign(lex, parseExp(lex)));
if (lex.current() != tSemicolon)
lex.expect(tRCurl);
else
lex.eat(tSemicolon);
break;
}
}
ExpPtr parseLoop (Lexer& lex)
{
Span spStart, spEnd;
ExpPtr body;
spStart = lex.eat(tLoop).span;
ExpList sub;
sub.reserve(2);
if (lex.current() == tLCurl)
{
sub.push_back(body = parseBlock(lex));
}
else
{
sub.push_back(parseExp(lex));
sub.push_back(body = parseBlock(lex));
}
spEnd = body->span;
return Exp::make(eLoop, std::move(sub), spStart + spEnd);
}
ExpPtr parseExp (Lexer& lex)
{
Span spStart, spEnd;
ExpList vals;
ExpPtr e;
Token tok;
e = parseTerm(lex);
vals.push_back(e);
spStart = spEnd = e->span;
while (lex.current() == tIdent)
if (lex.current().isOperator())
{
// <op>
tok = lex.advance();
e = Exp::make(eVar, tok.str, bool(true), {}, tok.span);
vals.push_back(e);
// <term>
e = parseTerm(lex);
vals.push_back(e);
spEnd = e->span;
}
else
lex.expect("operator");
if (vals.size() == 1)
return vals[0];
// else if (vals.size() == 3)
// return Exp::make(eCall, { vals[1], vals[0], vals[2] },
// spStart + spEnd);
else
return Exp::make(eInfix, vals, spStart + spEnd);
}
ExpPtr parseList (Lexer& lex)
{
Span spStart, spEnd;
ExpList vals;
spStart = lex.eat(tLBrack).span;
while (lex.current() != tRBrack)
{
vals.push_back(parseExp(lex));
if (lex.current() == tComma)
lex.advance();
else
break;
}
spEnd = lex.eat(tRBrack).span;
return Exp::make(eList, std::move(vals), spStart + spEnd);
}
ExpPtr parseTuple (Lexer& lex)
{
ExpList exps;
ExpPtr e;
Span spStart, spEnd;
spStart = lex.eat(tLParen).span;
while (lex.current() != tRParen)
{
e = parseExp(lex);
exps.push_back(e);
if (lex.current() == tComma)
lex.advance();
else
break;
}
spEnd = lex.eat(tRParen).span;
return Exp::make(eTuple, exps, spStart + spEnd);
}
