### 3.2.1 accidental-interface

A single accidental.

#### User settable properties:

> `alteration` (number)

>   Alteration numbers for accidental.

> `avoid-slur` (symbol)

>   Method of handling slur collisions. Choices are `inside`, `outside`, `around`, and `ignore`. `inside` adjusts the slur if needed to keep the grob inside the slur. `outside` moves the grob vertically to the outside of the slur. `around` moves the grob vertically to the outside of the slur only if there is a collision. `ignore` does not move either. In grobs whose notational significance depends on vertical position (such as accidentals, clefs, etc.), `outside` and `around` behave like `ignore`.

> `glyph-name-alist` (list)

>   An alist of key-string pairs.

> `glyph-name` (string)

>   The glyph name within the font.

>   In the context of (span) bar lines, glyph-name represents a processed form of `glyph`, where decisions about line breaking etc. are already taken.

> `hide-tied-accidental-after-break` (boolean)

>   If set, an accidental that appears on a tied note after a line break will not be displayed.

> `parenthesized` (boolean)

>   Parenthesize this grob.

> `restore-first` (boolean)

>   Print a natural before the accidental.

#### Internal properties:

> `forced` (boolean)

>   Manually forced accidental.

> `tie` (graphical (layout) object)

>   A pointer to a `Tie` object.

This grob interface is used in the following graphical object(s): Accidental, AccidentalCautionary, AccidentalSuggestion, AmbitusAccidental and TrillPitchAccidental.

#### Internals Reference v2.18.2 (稳定分支).