diff --git a/Cargo.toml b/Cargo.toml
index 473d272..e60dbc6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,6 +8,7 @@ crc = "1.0.0"
 nom = "4.0.0"
 pelite = "0.7.0"
 regex = "1.0.5"
+unicase = "2.2.0"
 
 [dev-dependencies]
 tempfile = "3.0.0"
diff --git a/src/function/mod.rs b/src/function/mod.rs
index 32ab9c8..b2c3c6e 100644
--- a/src/function/mod.rs
+++ b/src/function/mod.rs
@@ -1,6 +1,7 @@
 use std::path::PathBuf;
 
 use regex::Regex;
+use unicase::eq;
 
 pub mod eval;
 pub mod parse;
@@ -26,3 +27,251 @@ pub enum Function {
     Checksum(PathBuf, u32),
     Version(PathBuf, String, ComparisonOperator),
 }
+
+impl PartialEq for Function {
+    fn eq(&self, other: &Function) -> bool {
+        use Function::*;
+        match (self, other) {
+            (FilePath(p1), FilePath(p2)) => eq(&p1.to_string_lossy(), &p2.to_string_lossy()),
+            (FileRegex(p1, r1), FileRegex(p2, r2)) => {
+                eq(r1.as_str(), r2.as_str()) && eq(&p1.to_string_lossy(), &p2.to_string_lossy())
+            }
+            (ActivePath(p1), ActivePath(p2)) => eq(&p1.to_string_lossy(), &p2.to_string_lossy()),
+            (ActiveRegex(r1), ActiveRegex(r2)) => eq(r1.as_str(), r2.as_str()),
+            (Many(p1, r1), Many(p2, r2)) => {
+                eq(r1.as_str(), r2.as_str()) && eq(&p1.to_string_lossy(), &p2.to_string_lossy())
+            }
+            (ManyActive(r1), ManyActive(r2)) => eq(r1.as_str(), r2.as_str()),
+            (Checksum(p1, c1), Checksum(p2, c2)) => {
+                c1 == c2 && eq(&p1.to_string_lossy(), &p2.to_string_lossy())
+            }
+            (Version(p1, v1, c1), Version(p2, v2, c2)) => {
+                c1 == c2 && eq(&v1, &v2) && eq(&p1.to_string_lossy(), &p2.to_string_lossy())
+            }
+            _ => false,
+        }
+    }
+}
+
+impl Eq for Function {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn regex(string: &str) -> Regex {
+        Regex::new(string).unwrap()
+    }
+
+    #[test]
+    fn function_eq_for_file_path_should_check_pathbuf() {
+        assert_eq!(
+            Function::FilePath("Blank.esm".into()),
+            Function::FilePath("Blank.esm".into())
+        );
+
+        assert_ne!(
+            Function::FilePath("Blank.esp".into()),
+            Function::FilePath("Blank.esm".into())
+        );
+    }
+
+    #[test]
+    fn function_eq_for_file_path_should_be_case_insensitive_on_pathbuf() {
+        assert_eq!(
+            Function::FilePath("Blank.esm".into()),
+            Function::FilePath("blank.esm".into())
+        );
+    }
+
+    #[test]
+    fn function_eq_for_file_regex_should_check_pathbuf_and_regex() {
+        assert_eq!(
+            Function::FileRegex("subdir".into(), regex("blank.*")),
+            Function::FileRegex("subdir".into(), regex("blank.*"))
+        );
+
+        assert_ne!(
+            Function::FileRegex("subdir".into(), regex("blank.*")),
+            Function::FileRegex("other".into(), regex("blank.*"))
+        );
+        assert_ne!(
+            Function::FileRegex("subdir".into(), regex("blank.*")),
+            Function::FileRegex("subdir".into(), regex(".*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_file_regex_should_be_case_insensitive_on_pathbuf_and_regex() {
+        assert_eq!(
+            Function::FileRegex("subdir".into(), regex("blank.*")),
+            Function::FileRegex("Subdir".into(), regex("Blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_active_path_should_check_pathbuf() {
+        assert_eq!(
+            Function::ActivePath("Blank.esm".into()),
+            Function::ActivePath("Blank.esm".into())
+        );
+
+        assert_ne!(
+            Function::ActivePath("Blank.esp".into()),
+            Function::ActivePath("Blank.esm".into())
+        );
+    }
+
+    #[test]
+    fn function_eq_for_active_path_should_be_case_insensitive_on_pathbuf() {
+        assert_eq!(
+            Function::ActivePath("Blank.esm".into()),
+            Function::ActivePath("blank.esm".into())
+        );
+    }
+
+    #[test]
+    fn function_eq_active_path_should_not_be_equal_to_file_path_with_same_pathbuf() {
+        assert_ne!(
+            Function::ActivePath("Blank.esm".into()),
+            Function::FilePath("Blank.esm".into())
+        );
+    }
+
+    #[test]
+    fn function_eq_for_active_regex_should_check_regex() {
+        assert_eq!(
+            Function::ActiveRegex(regex("blank.*")),
+            Function::ActiveRegex(regex("blank.*"))
+        );
+
+        assert_ne!(
+            Function::ActiveRegex(regex("blank.*")),
+            Function::ActiveRegex(regex(".*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_active_regex_should_be_case_insensitive_on_regex() {
+        assert_eq!(
+            Function::ActiveRegex(regex("blank.*")),
+            Function::ActiveRegex(regex("Blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_many_should_check_pathbuf_and_regex() {
+        assert_eq!(
+            Function::Many("subdir".into(), regex("blank.*")),
+            Function::Many("subdir".into(), regex("blank.*"))
+        );
+
+        assert_ne!(
+            Function::Many("subdir".into(), regex("blank.*")),
+            Function::Many("subdir".into(), regex(".*"))
+        );
+        assert_ne!(
+            Function::Many("subdir".into(), regex("blank.*")),
+            Function::Many("other".into(), regex("blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_many_should_be_case_insensitive_on_pathbuf_and_regex() {
+        assert_eq!(
+            Function::FileRegex("subdir".into(), regex("blank.*")),
+            Function::FileRegex("Subdir".into(), regex("Blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_many_should_not_be_equal_to_file_regex_with_same_pathbuf_and_regex() {
+        assert_ne!(
+            Function::Many("subdir".into(), regex("blank.*")),
+            Function::FileRegex("subdir".into(), regex("blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_many_active_should_check_regex() {
+        assert_eq!(
+            Function::ManyActive(regex("blank.*")),
+            Function::ManyActive(regex("blank.*"))
+        );
+
+        assert_ne!(
+            Function::ManyActive(regex("blank.*")),
+            Function::ManyActive(regex(".*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_many_active_should_be_case_insensitive_on_regex() {
+        assert_eq!(
+            Function::ManyActive(regex("blank.*")),
+            Function::ManyActive(regex("Blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_many_active_should_not_be_equal_to_active_regex_with_same_regex() {
+        assert_ne!(
+            Function::ManyActive(regex("blank.*")),
+            Function::ActiveRegex(regex("blank.*"))
+        );
+    }
+
+    #[test]
+    fn function_eq_for_checksum_should_check_pathbuf_and_crc() {
+        assert_eq!(
+            Function::Checksum("Blank.esm".into(), 1),
+            Function::Checksum("Blank.esm".into(), 1)
+        );
+
+        assert_ne!(
+            Function::Checksum("Blank.esm".into(), 1),
+            Function::Checksum("Blank.esm".into(), 2)
+        );
+        assert_ne!(
+            Function::Checksum("Blank.esm".into(), 1),
+            Function::Checksum("Blank.esp".into(), 1)
+        );
+    }
+
+    #[test]
+    fn function_eq_for_checksum_should_be_case_insensitive_on_pathbuf() {
+        assert_eq!(
+            Function::Checksum("Blank.esm".into(), 1),
+            Function::Checksum("blank.esm".into(), 1)
+        );
+    }
+
+    #[test]
+    fn function_eq_for_version_should_check_pathbuf_version_and_comparator() {
+        assert_eq!(
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::Equal),
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::Equal)
+        );
+
+        assert_ne!(
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::Equal),
+            Function::Version("Blank.esp".into(), "1".into(), ComparisonOperator::Equal)
+        );
+        assert_ne!(
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::Equal),
+            Function::Version("Blank.esm".into(), "2".into(), ComparisonOperator::Equal)
+        );
+        assert_ne!(
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::Equal),
+            Function::Version("Blank.esm".into(), "1".into(), ComparisonOperator::NotEqual)
+        );
+    }
+
+    #[test]
+    fn function_eq_for_version_should_be_case_insensitive_on_pathbuf_and_version() {
+        assert_eq!(
+            Function::Version("Blank.esm".into(), "A".into(), ComparisonOperator::Equal),
+            Function::Version("blank.esm".into(), "a".into(), ComparisonOperator::Equal)
+        );
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 660e015..4cfd87d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,6 +3,7 @@ extern crate crc;
 extern crate nom;
 extern crate pelite;
 extern crate regex;
+extern crate unicase;
 
 #[cfg(test)]
 extern crate tempfile;