feat(namedTemplate): new function

src/string.test.ts

@@ -1,5 +1,5 @@
 import { expect, it } from 'vitest'
-import { capitalize, ensurePrefix, ensureSuffix, slash, template } from './string'
+import { capitalize, ensurePrefix, ensureSuffix, namedTemplate, slash, template } from './string'
 
 it('template', () => {
   expect(
@@ -34,6 +34,46 @@ it('template', () => {
   ).toEqual('Hi')
 })
 
+it('namedTemplate', () => {
+  expect(
+    namedTemplate(
+      '{greet}! My name is {name}.',
+      { greet: 'Hello', name: 'Anthony' },
+    ),
+  ).toEqual('Hello! My name is Anthony.')
+
+  expect(
+    namedTemplate(
+      '{a} + {b} = {result}',
+      { a: 1, b: 2, result: 3 }
+    ),
+  ).toEqual('1 + 2 = 3')
+
+  // Without fallback return the variable name
+  expect(
+    namedTemplate(
+      '{10}',
+      {},
+    ),
+  ).toEqual('10')
+
+  expect(
+    namedTemplate(
+      '{10}',
+      {},
+      'unknown'
+    ),
+  ).toEqual('unknown')
+
+  expect(
+    namedTemplate(
+      '{10}',
+      {},
+      ''
+    ),
+  ).toEqual('')
+})
+
 it('slash', () => {
   expect(slash('\\123')).toEqual('/123')
   expect(slash('\\\\')).toEqual('//')

src/string.ts

@@ -51,6 +51,25 @@ export function template(str: string, ...args: any[]): string {
   })
 }
 
+/**
+ * Dead simple named template engine, just like Python's
+ *
+ * @category String
+ * @example
+ * ```
+ * const result = template(
+ *   '{greet}! My name is {name}.',
+ *   { greet: 'Hello', name: 'Anthony' }
+ * ) // Hello! My name is Anthony.
+ * ```
+ */
+export function namedTemplate(str: string, vars: Record<string, any>, fallback: null | undefined | string = null): string {
+  return str.replace(
+    /{(\w+)}/g,
+    (_, variable) => vars[variable] || (fallback ?? variable),
+  )
+}
+
 // port from nanoid
 // https://github.com/ai/nanoid
 const urlAlphabet = 'useandom-26T198340PX75pxJACKVERYMINDBUSHWOLF_GQZbfghjklqvwyzrict'