diff --git a/src/value/parse.rs b/src/value/parse.rs
index 04c6520..7597b7b 100644
--- a/src/value/parse.rs
+++ b/src/value/parse.rs
@@ -378,7 +378,27 @@ fn single_value<I: Iterator<Item = Token>>(
                     span: next.span.merge(val.span),
                 }
             }
-            _ => todo!(),
+            Op::And => {
+                Spanned {
+                    node: Value::Ident(
+                        "and".into(),
+                        QuoteKind::None,
+                    ),
+                    span: next.span,
+                }
+            }
+            Op::Or => {
+                Spanned {
+                    node: Value::Ident(
+                        "or".into(),
+                        QuoteKind::None,
+                    ),
+                    span: next.span,
+                }
+            }
+            _ => {
+                return Err(("Expected expression.", next.span).into());
+            }
         },
         IntermediateValue::Whitespace => unreachable!(),
         IntermediateValue::Comma => return Err(("Expected expression.", span).into()),
diff --git a/tests/and.rs b/tests/and.rs
index 36d89f2..dd48b9f 100644
--- a/tests/and.rs
+++ b/tests/and.rs
@@ -40,3 +40,14 @@ test!(
     "a {\n  color: 1 and 2 and 3;\n}\n",
     "a {\n  color: 3;\n}\n"
 );
+test!(
+    part_of_binop,
+    "a {\n  color: 1 - and;\n}\n",
+    "a {\n  color: 1-and;\n}\n"
+);
+test!(
+    #[ignore = "casing is not preserved for keyword operators"]
+    part_of_binop_casing,
+    "a {\n  color: 1 - AND;\n}\n",
+    "a {\n  color: 1-AND;\n}\n"
+);
diff --git a/tests/error.rs b/tests/error.rs
index 8acb405..72d8124 100644
--- a/tests/error.rs
+++ b/tests/error.rs
@@ -130,3 +130,35 @@ error!(
     tilde_in_value,
     "a {color: ~a;}", "Error: Expected expression."
 );
+error!(
+    subtract_rem,
+    "a {color: 5 - %;}", "Error: Expected expression."
+);
+error!(
+    operator_eq,
+    "a {color: 5 - ==;}", "Error: Expected expression."
+);
+error!(
+    operator_ne,
+    "a {color: 5 - !=;}", "Error: Expected expression."
+);
+error!(
+    operator_gt,
+    "a {color: 5 - >;}", "Error: Expected expression."
+);
+error!(
+    operator_lt,
+    "a {color: 5 - <;}", "Error: Expected expression."
+);
+error!(
+    operator_ge,
+    "a {color: 5 - >=;}", "Error: Expected expression."
+);
+error!(
+    operator_le,
+    "a {color: 5 - <=;}", "Error: Expected expression."
+);
+error!(
+    operator_mul,
+    "a {color: 5 - *;}", "Error: Expected expression."
+);
diff --git a/tests/or.rs b/tests/or.rs
index f0ade8e..2aaa7b2 100644
--- a/tests/or.rs
+++ b/tests/or.rs
@@ -48,3 +48,14 @@ test!(
     "a {\n  color: 1 or 2 or 3;\n}\n",
     "a {\n  color: 1;\n}\n"
 );
+test!(
+    part_of_binop,
+    "a {\n  color: 1 - or;\n}\n",
+    "a {\n  color: 1-or;\n}\n"
+);
+test!(
+    #[ignore = "casing is not preserved for keyword operators"]
+    part_of_binop_casing,
+    "a {\n  color: 1 - OR;\n}\n",
+    "a {\n  color: 1-OR;\n}\n"
+);