Array Identifier Should Be Expression

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

tree-sitter-p4/grammar.js

@@ -94,7 +94,7 @@ export default grammar({
         transitionSelectionExpression: $ => choice($.identifier, $.selectExpression),
         keysetExpression: $ => $.expression,
         binaryOperatorExpression: $ => choice($.binaryEqualOperatorExpression),
-        arrayAccessExpression: $=> seq($.identifier, $.open_bracket, $.expression, $.close_bracket),
+        arrayAccessExpression: $=> seq($.expression, $.open_bracket, $.expression, $.close_bracket),
 
         // Binary Operations
         binaryEqualOperatorExpression: $ => prec.left(2, seq($.expression, $.double_equal, $.expression)),

tree-sitter-p4/test/corpus/expressions.txt

@@ -144,7 +144,9 @@ parser simple() {
        (expressionStatement
         (expression
          (arrayAccessExpression
+          (expression
            (identifier)
+          )
           (open_bracket)
           (expression
            (integer)