From 8907e0eccae190d32eae642765610eabbfd62c92 Mon Sep 17 00:00:00 2001 From: Egor Tensin Date: Tue, 31 Dec 2019 20:31:15 +0300 Subject: parser: refactoring --- server/parser/parser.hpp | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/server/parser/parser.hpp b/server/parser/parser.hpp index 596f84f..7d6f31d 100644 --- a/server/parser/parser.hpp +++ b/server/parser/parser.hpp @@ -41,25 +41,30 @@ private: double exec_expr(double lhs, unsigned min_prec) { for (auto op = peek_operator(); op.has_value() && op->get_precedence() >= min_prec;) { - const auto lhs_op = *op; + const auto prev = *op; + const auto prev_prec = prev.get_precedence(); + m_lexer.drop_token(); auto rhs = exec_primary(); for (op = peek_operator(); op.has_value(); op = peek_operator()) { - const auto op_prec = op->get_precedence(); - const auto lhs_prec = lhs_op.get_precedence(); - const auto ok_left_assoc = op->is_left_associative() && op_prec > lhs_prec; - const auto ok_right_assoc = op->is_right_associative() && op_prec == lhs_prec; - const auto ok = ok_left_assoc || ok_right_assoc; - - if (!ok) { - break; + const auto next = *op; + const auto next_prec = next.get_precedence(); + + { + const auto acc_left_assoc = next.is_left_associative() && next_prec > prev_prec; + const auto acc_right_assoc = next.is_right_associative() && next_prec == prev_prec; + const auto acc = acc_left_assoc || acc_right_assoc; + + if (!acc) { + break; + } } - rhs = exec_expr(rhs, op->get_precedence()); + rhs = exec_expr(rhs, next_prec); } - lhs = lhs_op.exec(lhs, rhs); + lhs = prev.exec(lhs, rhs); } return lhs; } -- cgit v1.2.3