diff --git a/lib/operators.js b/lib/operators.js
index 9370ff3..8899c4e 100644
--- a/lib/operators.js
+++ b/lib/operators.js
@@ -326,7 +326,7 @@ function processOperation(left, right, operator) {
 			if (right == 0) opResult = left;
 		}
 		// !a, ~a
-		else if (operator == '~' || operator == '~') {
+		else if (operator == '!' || operator == '~') {
 			opResult = operator + right
 		}
 		else if (operator == '*') {
diff --git a/test/api.js b/test/api.js
index 63b8009..3b7fc5f 100644
--- a/test/api.js
+++ b/test/api.js
@@ -28,6 +28,9 @@ var source = `
 		xy.xy *= uv.yx;
 		gl_Position = vec4(position.yx / 2.0, 0, 1);
 		gl_FragColor[0] = gl_FragCoord[0] / gl_Position.length();
+
+		bool foo = true;
+		bool bar = !foo == false && ~foo || foo;
 		return;
 	}
 
@@ -67,6 +70,8 @@ var result = `
 		xy = new Float32Array([xy[0] * uv[1], xy[1] * uv[0]]);
 		(gl_Position[0] = position[1] / 2.0, gl_Position[1] = position[0] / 2.0, gl_Position[2] = 0, gl_Position[3] = 1, gl_Position);
 		gl_FragColor[0] = gl_FragCoord[0] / 4;
+		var foo = true;
+		var bar = (!foo == false) && (~foo || foo);
 		return;
 	};