--- url: /reference/Interface.RolldownMagicString.md --- # Interface: RolldownMagicString ## Extends * `BindingMagicString` ## Properties ### isRolldownMagicString * **Type**: `true` ## Accessors ### filename #### Get Signature * **Type**: () => `string` | `null` ##### Returns `string` | `null` #### Inherited from `NativeBindingMagicString.filename` *** ### ignoreList #### Get Signature * **Type**: () => `boolean` ##### Returns `boolean` #### Inherited from `NativeBindingMagicString.ignoreList` *** ### indentExclusionRanges #### Get Signature * **Type**: () => `number`\[] | `number`\[]\[] | `null` ##### Returns `number`\[] | `number`\[]\[] | `null` #### Inherited from `NativeBindingMagicString.indentExclusionRanges` *** ### offset #### Get Signature * **Type**: () => `number` ##### Returns `number` #### Set Signature * **Type**: (`offset`: `number`) => `void` ##### Parameters ###### offset `number` ##### Returns `void` #### Inherited from `NativeBindingMagicString.offset` *** ### original #### Get Signature * **Type**: () => `string` ##### Returns `string` #### Inherited from `NativeBindingMagicString.original` ## Methods ### append() * **Type**: (`content`: `string`) => `this` #### Parameters ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.append` *** ### appendLeft() * **Type**: (`index`: `number`, `content`: `string`) => `this` #### Parameters ##### index `number` ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.appendLeft` *** ### appendRight() * **Type**: (`index`: `number`, `content`: `string`) => `this` #### Parameters ##### index `number` ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.appendRight` *** ### clone() * **Type**: () => `BindingMagicString` Returns a clone of the MagicString instance. #### Returns `BindingMagicString` #### Inherited from `NativeBindingMagicString.clone` *** ### generateDecodedMap() * **Type**: (`options?`: `BindingSourceMapOptions` | `null`) => `BindingDecodedMap` Generates a decoded source map for the transformations applied to this MagicString. Returns a BindingDecodedMap object with mappings as an array of arrays. #### Parameters ##### options? `BindingSourceMapOptions` | `null` #### Returns `BindingDecodedMap` #### Inherited from `NativeBindingMagicString.generateDecodedMap` *** ### generateMap() * **Type**: (`options?`: `BindingSourceMapOptions` | `null`) => `BindingSourceMap` Generates a source map for the transformations applied to this MagicString. Returns a BindingSourceMap object with version, file, sources, sourcesContent, names, mappings. #### Parameters ##### options? `BindingSourceMapOptions` | `null` #### Returns `BindingSourceMap` #### Inherited from `NativeBindingMagicString.generateMap` *** ### getIndentString() * **Type**: () => `string` Returns the guessed indentation string, or `\t` if none is found. #### Returns `string` #### Inherited from `NativeBindingMagicString.getIndentString` *** ### hasChanged() * **Type**: () => `boolean` #### Returns `boolean` #### Inherited from `NativeBindingMagicString.hasChanged` *** ### indent() * **Type**: (`indentor?`: `string` | `null`, `options?`: `BindingIndentOptions` | `null`) => `this` #### Parameters ##### indentor? `string` | `null` ##### options? `BindingIndentOptions` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.indent` *** ### insert() * **Type**: (`index`: `number`, `content`: `string`) => `void` Deprecated method that throws an error directing users to use prependRight or appendLeft. This matches the original magic-string API which deprecated this method. #### Parameters ##### index `number` ##### content `string` #### Returns `void` #### Inherited from `NativeBindingMagicString.insert` *** ### isEmpty() * **Type**: () => `boolean` #### Returns `boolean` #### Inherited from `NativeBindingMagicString.isEmpty` *** ### lastChar() * **Type**: () => `string` Returns the last character of the generated string, or an empty string if empty. #### Returns `string` #### Inherited from `NativeBindingMagicString.lastChar` *** ### lastLine() * **Type**: () => `string` Returns the content after the last newline in the generated string. #### Returns `string` #### Inherited from `NativeBindingMagicString.lastLine` *** ### length() * **Type**: () => `number` #### Returns `number` #### Inherited from `NativeBindingMagicString.length` *** ### move() * **Type**: (`start`: `number`, `end`: `number`, `index`: `number`) => `this` Alias for `relocate` to match the original magic-string API. Moves the characters from `start` to `end` to `index`. Returns `this` for method chaining. #### Parameters ##### start `number` ##### end `number` ##### index `number` #### Returns `this` #### Inherited from `NativeBindingMagicString.move` *** ### overwrite() * **Type**: (`start`: `number`, `end`: `number`, `content`: `string`, `options?`: `BindingOverwriteOptions` | `null`) => `this` #### Parameters ##### start `number` ##### end `number` ##### content `string` ##### options? `BindingOverwriteOptions` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.overwrite` *** ### prepend() * **Type**: (`content`: `string`) => `this` #### Parameters ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.prepend` *** ### prependLeft() * **Type**: (`index`: `number`, `content`: `string`) => `this` #### Parameters ##### index `number` ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.prependLeft` *** ### prependRight() * **Type**: (`index`: `number`, `content`: `string`) => `this` #### Parameters ##### index `number` ##### content `string` #### Returns `this` #### Inherited from `NativeBindingMagicString.prependRight` *** ### relocate() * **Type**: (`start`: `number`, `end`: `number`, `to`: `number`) => `this` #### Parameters ##### start `number` ##### end `number` ##### to `number` #### Returns `this` #### Inherited from `NativeBindingMagicString.relocate` *** ### remove() * **Type**: (`start`: `number`, `end`: `number`) => `this` #### Parameters ##### start `number` ##### end `number` #### Returns `this` #### Inherited from `NativeBindingMagicString.remove` *** ### replace() * **Type**: (`from`: `string` | `RegExp`, `to`: `string`) => `this` Accepts a string or RegExp pattern. RegExp supports `$&`, `$$`, and `$N` substitutions. #### Parameters ##### from `string` | `RegExp` ##### to `string` #### Returns `this` #### Overrides `NativeBindingMagicString.replace` *** ### replaceAll() * **Type**: (`from`: `string` | `RegExp`, `to`: `string`) => `this` Accepts a string or RegExp pattern. RegExp must have the global (`g`) flag. #### Parameters ##### from `string` | `RegExp` ##### to `string` #### Returns `this` #### Overrides `NativeBindingMagicString.replaceAll` *** ### replaceRegex() * **Type**: (`from`: `RegExp`, `to`: `string`) => `number` Returns the UTF-16 offset past the last match, or -1 if no match was found. The JS wrapper uses this to update `lastIndex` on the caller's RegExp. Global/sticky behavior is derived from the regex's own flags. #### Parameters ##### from `RegExp` ##### to `string` #### Returns `number` #### Inherited from `NativeBindingMagicString.replaceRegex` *** ### reset() * **Type**: (`start`: `number`, `end`: `number`) => `this` Resets the portion of the string from `start` to `end` to its original content. This undoes any modifications made to that range. Supports negative indices (counting from the end). #### Parameters ##### start `number` ##### end `number` #### Returns `this` #### Inherited from `NativeBindingMagicString.reset` *** ### slice() * **Type**: (`start?`: `number` | `null`, `end?`: `number` | `null`) => `string` Returns the content between the specified UTF-16 code unit positions (JS string indices). Supports negative indices (counting from the end). When an index falls in the middle of a surrogate pair, the lone surrogate is included in the result (matching the original magic-string / JS behavior). This is done by returning a UTF-16 encoded JS string via `napi_create_string_utf16`. #### Parameters ##### start? `number` | `null` ##### end? `number` | `null` #### Returns `string` #### Inherited from `NativeBindingMagicString.slice` *** ### snip() * **Type**: (`start`: `number`, `end`: `number`) => `BindingMagicString` Returns a clone with content outside the specified range removed. #### Parameters ##### start `number` ##### end `number` #### Returns `BindingMagicString` #### Inherited from `NativeBindingMagicString.snip` *** ### toString() * **Type**: () => `string` #### Returns `string` #### Inherited from `NativeBindingMagicString.toString` *** ### trim() * **Type**: (`charType?`: `string` | `null`) => `this` Trims whitespace or specified characters from the start and end. #### Parameters ##### charType? `string` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.trim` *** ### trimEnd() * **Type**: (`charType?`: `string` | `null`) => `this` Trims whitespace or specified characters from the end. #### Parameters ##### charType? `string` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.trimEnd` *** ### trimLines() * **Type**: () => `this` Trims newlines from the start and end. #### Returns `this` #### Inherited from `NativeBindingMagicString.trimLines` *** ### trimStart() * **Type**: (`charType?`: `string` | `null`) => `this` Trims whitespace or specified characters from the start. #### Parameters ##### charType? `string` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.trimStart` *** ### update() * **Type**: (`start`: `number`, `end`: `number`, `content`: `string`, `options?`: `BindingUpdateOptions` | `null`) => `this` #### Parameters ##### start `number` ##### end `number` ##### content `string` ##### options? `BindingUpdateOptions` | `null` #### Returns `this` #### Inherited from `NativeBindingMagicString.update`