feat(Epoch): move gcd to utils

Author: phroi

packages/core/src/ckb/epoch.ts

@@ -3,6 +3,7 @@ import { Zero } from "../fixedPoint/index.js";
 import { type Hex, type HexLike } from "../hex/index.js";
 import { mol } from "../molecule/index.js";
 import { numFrom, NumLike, type Num } from "../num/index.js";
+import { gcd } from "../utils/index.js";
 
 /**
  * @deprecated use `Epoch.from` instead
@@ -293,19 +294,3 @@ export class Epoch extends mol.Entity.Base<EpochLike, Epoch>() {
  * 4 hours * 60 minutes per hour * 60 seconds per minute * 1000 milliseconds per second.
  */
 const epochInMilliseconds = numFrom(14400000); // (Number.isSafeInteger(14400000) === true)
-
-/**
- * Calculate the greatest common divisor (GCD) of two Num values using the Euclidean algorithm.
- *
- * @param a - First operand.
- * @param b - Second operand.
- * @returns GCD(a, b) as a Num.
- */
-function gcd(a: Num, b: Num): Num {
-  a = a < Zero ? -a : a;
-  b = b < Zero ? -b : b;
-  while (b !== Zero) {
-    [a, b] = [b, a % b];
-  }
-  return a;
-}

packages/core/src/utils/index.ts

@@ -1,4 +1,5 @@
-import { NumLike, numFrom, numToHex } from "../num/index.js";
+import { Zero } from "../fixedPoint/index.js";
+import { NumLike, numFrom, numToHex, type Num } from "../num/index.js";
 
 /**
  * A type safe way to apply a transformer on a value if it's not empty.
@@ -264,3 +265,19 @@ export function stringify(val: unknown) {
     return value;
   });
 }
+
+/**
+ * Calculate the greatest common divisor (GCD) of two Num values using the Euclidean algorithm.
+ *
+ * @param a - First operand.
+ * @param b - Second operand.
+ * @returns GCD(a, b) as a Num.
+ */
+export function gcd(a: Num, b: Num): Num {
+  a = a < Zero ? -a : a;
+  b = b < Zero ? -b : b;
+  while (b !== Zero) {
+    [a, b] = [b, a % b];
+  }
+  return a;
+}