feat: add unary operators and variable assignment with precedence handling

Implement unary negation for numbers and logical not for booleans, introduce PREC_ASSIGNMENT and PREC_UNARY precedence levels, refactor parse functions to accept allowAssignment parameter, add assignment tests for global/local/chained/error cases, and update if-syntax to support statement branches and assignment in conditions.
2013-11-13 15:10:52 +00:00
parent 944591339f
commit 7eabd40181
15 changed files with 281 additions and 115 deletions
@@ -23,6 +23,9 @@ io.write(false == 2 <= 1) // expect: true
 // >= has higher precedence than ==.
 io.write(false == 1 >= 2) // expect: true

+// Unary - has lower precedence than ..
+io.write(-"abc".count) // expect: -3
+
 // TODO(bob): %, associativity.

 // Using () for grouping.