1 files changed, 68 insertions, 0 deletions
diff --git a/src/math/function.rs b/src/math/function.rs
new file mode 100644
index 0000000..bd782f3
--- /dev/null
+++ b/src/math/function.rs
@@ -0,0 +1,68 @@
+use crate::math::{complex::Complex, context::Context};
+
+pub struct FunctionArgument {
+    args : Vec<Complex>,
+}
+
+impl FunctionArgument {
+    pub fn new(args: Vec<Complex>) -> Self {
+        Self { args }
+    }
+
+    pub fn get(&self, i : usize) -> Complex {
+        self.args[i]
+    }
+
+    pub fn len(&self) -> usize {
+        self.args.len()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.args.len() == 0
+    }
+
+    pub fn data(&self) -> &[Complex] {
+        &self.args
+    }
+}
+
+pub trait Function {
+    fn eval(&self, args: FunctionArgument, ctx: &Context) -> Result<Complex, String>;
+}
+
+#[macro_export]
+macro_rules! functions {
+    {$($x:expr => $y:expr), *} => {
+        {
+            let mut h : HashMap<String, Arc<dyn Function>> = HashMap::new();
+            $(
+                h.insert($x.to_string(), Arc::new($y));
+            )*
+            h
+        }
+    };
+}
+
+
+// Some default implementations
+impl<T> Function for T
+where
+    T: Fn(Complex) -> Complex,
+{
+    fn eval(&self, args: FunctionArgument, _ctx: &Context) -> Result<Complex, String> {
+        if args.len() == 1 {
+            Ok(self(args.get(0)))
+        } else {
+            Err("too many arguments".to_string())
+        }
+    }
+}
+
+
+pub struct EmptyFunction {}
+
+impl Function for EmptyFunction {
+    fn eval(&self, _args: FunctionArgument, _ctx: &Context) -> Result<Complex, String> {
+        Err("function not implemented in this scope".to_string())
+    }
+}