feat: work on fibonacci function, add = comparator.

README.md

@@ -76,7 +76,11 @@ mumble> sq 44
 mumble> def {sqsum} (@ {x y} {(+ (sq x) (sq y))})
 mumble> sqsum 2 3
 mumble> def {init} (@ {xs} { list((head xs)) } )
+mumble> def {unwrap} (@ {x} { head (list xx) } )
 mumble> init {1 2}
+mumble> ifelse 1 2 3
+mumble> ifelse 0 1 2 
+mumble> ifelse {1 2 3} (1) (1)
 ```
 
 ## To do
@@ -84,6 +88,7 @@ mumble> init {1 2}
 - [x] Define functions
 - [ ] Define if, = and >
 - [ ] Build fibonacci function
+  - Should look something like:  def {fib} (@ {x} { ifelse x (+ x (fib (- x 1))) 0 } )
 
 ## Gotchas
 

src/mumble.c

@@ -846,15 +846,35 @@ lispval* builtin_ifelse(lispval* v, lispenv* e)
     lispval* alternative = v->cell[2];
 		
 		if( choice->type == LISPVAL_NUM && choice->num == 0){
-			lispval* answer = clone_lispval(result);
+			lispval* answer = clone_lispval(alternative);
 			return answer;
 		}else {
-			lispval* answer = clone_lispval(alternative);
+			lispval* answer = clone_lispval(result);
 			return answer;
 		}
 }
 
-// Comparators: =, >
+// Comparators: =, > (also potentially <, >=, <=, <=)
+// For numbers. 
+
+lispval* builtin_equal(lispval* v, lispenv* e)
+{
+    // ifelse 1 {a} b
+    LISPVAL_ASSERT(v->count == 2, "Error: function = takes two numeric arguments. Try (= 1 2)");
+
+    lispval* a = v->cell[0];
+    lispval* b = v->cell[1];
+	  
+		LISPVAL_ASSERT(a->type == LISPVAL_NUM, "Error: Functio = only takes numeric arguments.");
+		LISPVAL_ASSERT(b->type == LISPVAL_NUM, "Error: Functio = only takes numeric arguments.");
+
+		if(a->num == b->num){
+			return lispval_num(1);
+		}else {
+			return lispval_num(0);
+		}
+}
+
 
 // Simple math ops
 lispval* builtin_math_ops(char* op, lispval* v, lispenv* e)
@@ -956,6 +976,7 @@ void lispenv_add_builtins(lispenv* env)
     lispenv_add_builtin("def", builtin_def, env);
     lispenv_add_builtin("@", builtin_define_lambda, env);
     lispenv_add_builtin("ifelse", builtin_ifelse, env);
+    lispenv_add_builtin("=", builtin_equal, env);
 }
 
 // Evaluate the lispval