1 files changed, 38 insertions, 4 deletions
diff --git a/src/function.rs b/src/function.rs
index 547ae0e..442d987 100644
--- a/src/function.rs
+++ b/src/function.rs
@@ -1,17 +1,51 @@
+use crate::complex::Complex;
+
 pub struct FunctionArgument {
-    args : Vec<f64>,
+    args : Vec<Complex>,
 }
 
 impl FunctionArgument {
-    pub fn new(args: Vec<f64>) -> Self {
+    pub fn new(args: Vec<Complex>) -> Self {
         Self { args }
     }
 
-    pub fn get(&self, i : usize) -> f64 {
+    pub fn get(&self, i : usize) -> Complex {
         self.args[i]
     }
+
+    pub fn len(&self) -> usize {
+        self.args.len()
+    }
 }
 
 pub trait Function {
-    fn eval(&self, args: FunctionArgument) -> f64;
+    fn eval(&self, args: FunctionArgument) -> Result<Complex, String>;
+}
+
+#[macro_export]
+macro_rules! functions {
+    ({$($x:expr => $y:expr), *}) => {
+        {
+            let mut h : HashMap<String, Box<dyn Function>> = HashMap::new();
+            $(
+                h.insert($x.to_string(), Box::new($y));
+            )*
+            h
+        }
+    };
+}
+
+
+// Some default implementations
+impl<T> Function for T
+where
+    T: Fn(Complex) -> Complex,
+{
+    fn eval(&self, args: FunctionArgument) -> Result<Complex, String> {
+        if args.len() == 1 {
+            Ok(self(args.get(0)))
+        } else {
+            Err("too many arguments".to_string())
+        }
+    }
 }