diff options
Diffstat (limited to 'shell/math.c')
| -rw-r--r-- | shell/math.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/shell/math.c b/shell/math.c index fa22bc4..077aba8 100644 --- a/shell/math.c +++ b/shell/math.c @@ -340,7 +340,20 @@ arith_apply(arith_state_t *math_state, operator op, var_or_num_t *numstack, var_ if (op == TOK_CONDITIONAL) /* Example: $((a ? b)) */ return "malformed ?: operator"; - /* Resolve name to value, if needed */ + if (PREC(op) < UNARYPREC) { + /* In binops a ~ b, variables are resolved left-to-right, + * resolve top_of_stack[-1] _before_ resolving top_of_stack[0] + */ + if (top_of_stack == numstack) /* need two arguments */ + goto syntax_err; + /* Unless it is =, resolve top_of_stack[-1] name to value */ + if (op != TOK_ASSIGN) { + err = arith_lookup_val(math_state, top_of_stack - 1); + if (err) + return err; + } + } + /* Resolve top_of_stack[0] name to value */ err = arith_lookup_val(math_state, top_of_stack); if (err) return err; @@ -360,20 +373,10 @@ arith_apply(arith_state_t *math_state, operator op, var_or_num_t *numstack, var_ /* Binary operators */ arith_t right_side_val; - /* Binary operators need two arguments */ - if (top_of_stack == numstack) - goto syntax_err; - /* ...and they pop one */ + /* Pop numstack */ NUMPTR = top_of_stack; /* this decrements NUMPTR */ top_of_stack--; /* now points to left side */ - if (op != TOK_ASSIGN) { - /* Resolve left side value (unless the op is '=') */ - err = arith_lookup_val(math_state, top_of_stack); - if (err) - return err; - } - right_side_val = rez; rez = top_of_stack->val; if (op == TOK_BOR || op == TOK_OR_ASSIGN) |