feat(tree): support parenthesis

3 files changed, 7 insertions, 1 deletions

diff --git a/example/input.txt b/example/input.txt
index cb3073b..ec70a41 100644
--- a/example/input.txt
+++ b/example/input.txt
@@ -1,6 +1,6 @@
 :a = 7
 :b = 4
-:result = :a + :b * 10 / 2
+:result = (:a + :b) * 10 / 2
 
 :x = 20
 :y = 3
diff --git a/src/elixir_math_parser.yrl b/src/elixir_math_parser.yrl
index 4900996..762cf4b 100644
--- a/src/elixir_math_parser.yrl
+++ b/src/elixir_math_parser.yrl
@@ -13,6 +13,8 @@ Terminals
   '*'
   '/'
   '='
+  '('
+  ')'
 .
 
 Rootsymbol
@@ -24,6 +26,7 @@ Left 300 '+'.
 Left 300 '-'.
 Left 400 '*'.
 Left 400 '/'.
+Left 600 '('.
 
 root -> assignments : '$1'.
 
@@ -38,6 +41,7 @@ expr -> expr '+' expr : {add_op, '$1', '$3'}.
 expr -> expr '-' expr : {sub_op, '$1', '$3'}.
 expr -> expr '*' expr : {mul_op, '$1', '$3'}.
 expr -> expr '/' expr : {div_op, '$1', '$3'}.
+expr -> '(' expr ')'  : '$2'.
 
 Erlang code.
 
diff --git a/src/elixir_math_parser_lexer.xrl b/src/elixir_math_parser_lexer.xrl
index a2980c8..8d7920a 100644
--- a/src/elixir_math_parser_lexer.xrl
+++ b/src/elixir_math_parser_lexer.xrl
@@ -9,6 +9,8 @@ Rules.
 \*            : {token, {'*',  TokenLine}}.
 \/            : {token, {'/',  TokenLine}}.
 \=            : {token, {'=',  TokenLine}}.
+\(            : {token, {'(',  TokenLine}}.
+\)            : {token, {')',  TokenLine}}.
 {NAME}        : {token, {atom, TokenLine, to_atom(TokenChars)}}.
 {INT}         : {token, {int,  TokenLine, TokenChars}}.
 {WHITESPACE}+ : skip_token.