> For the complete documentation index, see [llms.txt](https://radoslaw-medryk.gitbook.io/verifica/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://radoslaw-medryk.gitbook.io/verifica/predicates/built-in-predicates/isregexmatch.md).

# isRegexMatch

```typescript
isRegexMatch(regex)
```

Verifies if provided `Verificable` represents a string that matches provided `regex` object.

### Arguments:

* `regex` - required, of type `RegExp` 

### Possible errors:

#### If provided `Verificable` is not a string:

```typescript
{
    type: "isString",
    path: [/* ... */]
}
```

#### If provided `Verificable` is not matching provided `regex`:

```typescript
{
    type: "isRegexMatch",
    path: [/* ... */]
}
```

### Examples:

Each of examples uses this import statement:

```typescript
const { asVerificable, isValid, isRegexMatch } = require("verifica");
```

#### Null or undefined is not considered a string:

```typescript
const verificable = asVerificable(null);
isValid(verificable, isRegexMatch(/^[0-9]*$/)); // false
```

#### Number value is not considered a string as well:

```typescript
const verificable = asVerificable(123);
isValid(verificable, isRegexMatch(/^[0-9]*$/)); // false
```

#### Value not matching the `regex` is not matching the predicate:

```typescript
const verificable = asVerificable("abc");
isValid(verificable, isRegexMatch(/^[0-9]*$/)); // false
```

#### Value matching the `regex` matches the predicate:

```typescript
const verificable = asVerificable("123");
isValid(verificable, isRegexMatch(/^[0-9]*$/)); // true
```


---

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