Separates utils and helpers

__tests__/constants/anything.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * anything constant test

__tests__/constants/newline.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * newline constant test

__tests__/constants/number.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * number constant test

__tests__/constants/symbol.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * symbol constant test

__tests__/constants/whitespace.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * whitespace constant test

__tests__/constants/word.test.ts

@@ -1,5 +1,5 @@
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * word constant test

__tests__/sequences/anything.test.ts

@@ -1,6 +1,6 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * anything sequence test

__tests__/sequences/newlines.test.ts

@@ -1,6 +1,6 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * newlines sequence test

__tests__/sequences/numbers.test.ts

@@ -1,6 +1,6 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * numbers sequence test

__tests__/sequences/symbols.test.ts

@@ -1,6 +1,6 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * symbols sequence test

__tests__/sequences/whitespace.test.ts

@@ -1,6 +1,6 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
-import { formatInternalExpression } from '../../src/utils';
+import { formatInternalExpression } from '../../src/helpers';
 
 /**
  * whitespace sequence test

__tests__/utils/utils.test.ts

@@ -1,16 +1,15 @@
 import Sequences from '../../src/sequences';
 import Constants from '../../src/constants';
+import { or, anyOf } from '../../src/utils';
 import {
   escapeString,
   matches,
   wrapOptionalExpression,
   wrapOrExpression,
   validateExpression,
-  or,
   validateFlags,
   getGroupsByIndex,
-  anyOf,
-} from '../../src/utils';
+} from '../../src/helpers';
 
 /**
  * beginsWith test

package.json

@@ -1,6 +1,6 @@
 {
   "name": "exceptional-expressions",
-  "version": "0.2.1",
+  "version": "0.2.2",
   "description": "An incredible way to build efficient, concise and human readable regular expressions.",
   "keywords": [
     "typescript",

src/assertions.ts

@@ -0,0 +1,47 @@
+/**
+ * Assert that a value passed equals either null or undefined
+ *
+ * @param {any} val
+ * @param {string} message
+ */
+export const assertDoesntExist: (val: any, message?: string) => asserts val is null | undefined = (
+  val: any,
+  message?: string
+): asserts val is null | undefined => {
+  if (!(val === undefined || val === null)) {
+    throw new Error(message);
+  }
+};
+
+/**
+ * Asser that the value passed is not null or undefined
+ *
+ * @param {T} val
+ * @param {string} message
+ */
+export const assertExists: <T>(val: T, message?: string) => asserts val is NonNullable<T> = <T>(
+  val: T,
+  message?: string
+): asserts val is NonNullable<T> => {
+  if (val === undefined || val === null) {
+    throw new Error(message);
+  }
+};
+
+/**
+ * Assert that at least one of the values passed is not null or undefined
+ *
+ * @param {Array<T>} val
+ * @param {string} message
+ */
+export const assertOneExists: <T>(val: Array<T>, message?: string) => asserts val is T[] = <T>(
+  val: Array<T>,
+  message?: string
+): asserts val is T[] => {
+  for (const item of val) {
+    if (item !== undefined && item !== null) {
+      return;
+    }
+  }
+  throw new Error(message);
+};

src/constants.ts

@@ -7,7 +7,9 @@ export default {
   number: '~~\\d',
   symbol: '~~[\\-!\\$%±§#\\^@&*\\(\\)_+|~=`{}\\[\\]:";\'<>\\?,\\.\\/]',
   word: "~~[A-Za-z']+\\b",
-  anything: '~~.'
+  anything: '~~.',
+  lowercaseLetter: '~~(?:a-z)',
+  uppercaseLetter: '~~(?:A-Z)',
   // email:
   //   '~~(([^<>()[]\\.,;:s@"]+(.[^<>()[]\\.,;:s@"]+)*)|(".+"))@(([[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}])|(([a-zA-Z-0-9]+.)+[a-zA-Z]{2,}))'
 };

src/exceptional-expressions.ts

@@ -3,14 +3,14 @@ import {
   handleOptionalWrapping,
   validateExpression,
   wrapOrExpression,
-  assertExists,
-  assertOneExists,
-  assertDoesntExist,
   validateFlags,
   extractMatches,
   extractMatchesWithGroup,
   IGroupings,
-} from './utils';
+} from './helpers';
+
+import { assertExists, assertOneExists, assertDoesntExist } from './assertions';
+
 export default class ExpressionBuilder {
   private beginsWithExpression: string | null = null;
   private internal: Array<string> = [];