From 341ca6d69b979968b82fd8071cf57a7422a40fa6 Mon Sep 17 00:00:00 2001
From: Andrew Chin <achin@eminence32.net>
Date: Thu, 23 Nov 2023 15:33:27 -0500
Subject: [PATCH] Introduce DType::is_scalar function

---
 numbat/src/typechecker.rs | 6 +++---
 numbat/src/typed_ast.rs   | 5 ++++-
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/numbat/src/typechecker.rs b/numbat/src/typechecker.rs
index c44ff184..822e5b49 100644
--- a/numbat/src/typechecker.rs
+++ b/numbat/src/typechecker.rs
@@ -457,7 +457,7 @@ impl TypeChecker {
 
                 match *op {
                     ast::UnaryOperator::Factorial => {
-                        if dtype != DType::unity() {
+                        if !dtype.is_scalar() {
                             return Err(TypeCheckError::NonScalarFactorialArgument(
                                 expr.full_span(),
                                 dtype,
@@ -539,7 +539,7 @@ impl TypeChecker {
                     }
                     typed_ast::BinaryOperator::Power => {
                         let exponent_type = dtype(&rhs_checked)?;
-                        if exponent_type != DType::unity() {
+                        if !exponent_type.is_scalar() {
                             return Err(TypeCheckError::NonScalarExponent(
                                 rhs.full_span(),
                                 exponent_type,
@@ -547,7 +547,7 @@ impl TypeChecker {
                         }
 
                         let base_type = dtype(&lhs_checked)?;
-                        if base_type == DType::unity() {
+                        if base_type.is_scalar() {
                             // Skip evaluating the exponent if the lhs is a scalar. This allows
                             // for arbitrary (decimal) exponents, if the base is a scalar.
 
diff --git a/numbat/src/typed_ast.rs b/numbat/src/typed_ast.rs
index 297b46dc..0f856852 100644
--- a/numbat/src/typed_ast.rs
+++ b/numbat/src/typed_ast.rs
@@ -15,8 +15,11 @@ use crate::{
 pub type DType = BaseRepresentation;
 
 impl DType {
+    pub fn is_scalar(&self) -> bool {
+        self == &DType::unity()
+    }
     pub fn to_readable_type(&self, registry: &DimensionRegistry) -> m::Markup {
-        if self == &DType::unity() {
+        if self.is_scalar() {
             return m::type_identifier("Scalar");
         }