Rename types for consistency

src/ast.rs

@@ -2,12 +2,12 @@
 
 pub enum BinaryOperator
 {
-	Addition,
-	Subtraction,
-	Multiplication,
-	Division,
+	Add,
+	Subtract,
+	Multiply,
+	Divide,
 	Modulo,
-	Exponentiation,
+	Exponentiate,
 }
 
 pub enum ComparisonOperator
@@ -23,7 +23,7 @@ pub enum ComparisonOperator
 pub enum UnaryOperator
 {
 	AbsoluteValue,
-	Negation,
+	Negative,
 }
 
 // Primitives
@@ -153,13 +153,7 @@ pub struct Variable
 
 // Formulas
 
-pub struct Biconditional
-{
-	pub left: Box<Formula>,
-	pub right: Box<Formula>,
-}
-
-pub struct Comparison
+pub struct Compare
 {
 	pub operator: ComparisonOperator,
 	pub left: Box<Term>,
@@ -178,6 +172,12 @@ pub struct ForAll
 	pub argument: Box<Formula>,
 }
 
+pub struct IfAndOnlyIf
+{
+	pub left: Box<Formula>,
+	pub right: Box<Formula>,
+}
+
 pub struct Implies
 {
 	pub antecedent: Box<Formula>,
@@ -210,11 +210,11 @@ pub type Terms = Vec<Box<Term>>;
 pub enum Formula
 {
 	And(Formulas),
-	Biconditional(Biconditional),
 	Boolean(bool),
-	Comparison(Comparison),
+	Compare(Compare),
 	Exists(Exists),
 	ForAll(ForAll),
+	IfAndOnlyIf(IfAndOnlyIf),
 	Implies(Implies),
 	Not(Box<Formula>),
 	Or(Formulas),