static sl_node_base_t* for_expression(sl_parse_state_t* ps) { sl_node_base_t *lval, *expr, *body, *else_body = NULL; sl_node_seq_t* seq_lval; sl_token_t* tok; sl_parse_scope_t scope; expect_token(ps, SL_TOK_FOR); /* save current token to allow rewinding and erroring */ tok = peek_token(ps); lval = call_expression(ps); if(!sl_node_is_lval(lval)) { unexpected(ps, tok); } if(peek_token(ps)->type == SL_TOK_COMMA || peek_token(ps)->type == SL_TOK_FAT_COMMA) { seq_lval = sl_make_seq_node(ps); seq_lval->nodes[seq_lval->node_count++] = lval; while(peek_token(ps)->type == SL_TOK_COMMA || peek_token(ps)->type == SL_TOK_FAT_COMMA) { next_token(ps); if(seq_lval->node_count == seq_lval->node_capacity) { seq_lval->node_capacity *= 2; seq_lval->nodes = sl_realloc(ps->vm->arena, seq_lval->nodes, sizeof(sl_node_base_t*) * seq_lval->node_capacity); } tok = peek_token(ps); lval = call_expression(ps); if(!sl_node_is_lval(lval)) { unexpected(ps, tok); } seq_lval->nodes[seq_lval->node_count++] = lval; } lval = sl_make_array_node(ps, seq_lval->node_count, seq_lval->nodes); } expect_token(ps, SL_TOK_IN); expr = expression(ps); scope.prev = ps->scope; scope.flags = scope.prev->flags | SL_PF_CAN_NEXT_LAST; ps->scope = &scope; body = body_expression(ps); ps->scope = scope.prev; if(scope.flags & SL_PF_SCOPE_CLOSURE) { ps->scope->flags |= SL_PF_SCOPE_CLOSURE; } if(peek_token(ps)->type == SL_TOK_ELSE) { next_token(ps); else_body = body_expression(ps); } return sl_make_for_node(ps, lval, expr, body, else_body); }
static sl_node_base_t* use_expression(sl_parse_state_t* ps) { expect_token(ps, SL_TOK_USE); sl_node_base_t* node = call_expression(ps); if(node->type != SL_NODE_CONST) { error(ps, sl_make_cstring(ps->vm, "Expected constant reference in use expression"), token(ps)); } for(sl_node_base_t* i = node; i && i->type == SL_NODE_CONST; i = ((sl_node_const_t*)i)->obj) { i->type = SL_NODE_USE; } return node; }
static sl_node_base_t* inc_dec_expression(sl_parse_state_t* ps) { if(peek_token(ps)->type == SL_TOK_INCREMENT) { next_token(ps); return sl_make_prefix_mutate_node(ps, call_expression(ps), "succ"); } if(peek_token(ps)->type == SL_TOK_DECREMENT) { next_token(ps); return sl_make_prefix_mutate_node(ps, call_expression(ps), "pred"); } sl_node_base_t* lval = call_expression(ps); if(sl_node_is_mutable_lval(lval)) { if(peek_token(ps)->type == SL_TOK_INCREMENT) { next_token(ps); return sl_make_postfix_mutate_node(ps, lval, "succ"); } if(peek_token(ps)->type == SL_TOK_DECREMENT) { next_token(ps); return sl_make_postfix_mutate_node(ps, lval, "pred"); } } return lval; }
// Parse a postfix-expression. // // postfix-expression: // primary-expression // postfix-expression '.' id // postfix-expression '(' [expression-list] ')' // postfix-expression '[' expression ']' // // TODO: Add lots of stuff here. Expr& Parser::postfix_expression() { Expr* e = &primary_expression(); while (true) { if (lookahead() == tk::dot_tok) e = &dot_expression(*e); else if (lookahead() == tk::lparen_tok) e = &call_expression(*e); else if (lookahead() == tk::lbracket_tok) e = &subscript_expression(*e); else break; } return *e; }