diff --git a/lib/macro/internal/Cargo.toml b/lib/macro/internal/Cargo.toml
index 84de558..215b255 100644
--- a/lib/macro/internal/Cargo.toml
+++ b/lib/macro/internal/Cargo.toml
@@ -15,4 +15,4 @@ proc-macro = true
 
 [dependencies]
 data-encoding = { version = "2.3", path = "../..", default-features = false, features = ["alloc"] }
-syn = "1"
+syn = { version = "1", default-features = false, features = ["parsing", "proc-macro"] }
diff --git a/lib/macro/internal/src/lib.rs b/lib/macro/internal/src/lib.rs
index a7eaa72..bb1ff33 100644
--- a/lib/macro/internal/src/lib.rs
+++ b/lib/macro/internal/src/lib.rs
@@ -87,7 +87,7 @@ fn get_bool(map: &mut HashMap<String, TokenTree>, key: &str) -> Option<bool> {
     };
     match syn::parse::<syn::LitBool>(node.into()) {
         Ok(result) => Some(result.value),
-        _ => panic!("expected bool for padding"),
+        _ => panic!("expected bool for {}", key),
     }
 }
 
diff --git a/lib/macro/tests/lib.rs b/lib/macro/tests/lib.rs
index e007666..2d414af 100644
--- a/lib/macro/tests/lib.rs
+++ b/lib/macro/tests/lib.rs
@@ -76,3 +76,11 @@ fn base64_decode() {
     const OUTPUT: &'static [u8] = &data_encoding_macro::base64!("deadbeef");
     assert_eq!(OUTPUT, data_encoding::BASE64.decode(b"deadbeef").unwrap());
 }
+
+#[test]
+fn escaped_symbols() {
+    const BASE: data_encoding::Encoding = data_encoding_macro::new_encoding! {
+        symbols: "\x00\n\"\\",
+    };
+    assert_eq!(BASE.encode(b"K"), "\n\x00\"\\");
+}