# Rhythm and silence

## Duration comes first

| Value | Meaning | Accepted letter |
| --- | --- | --- |
| `1` | Whole note | `w` |
| `2` | Half note | `h` |
| `4` | Quarter note | `q` |
| `8` | Eighth note | `e` |
| `16` | Sixteenth note | `s` |
| `32` | Thirty-second note | `t` |
| `64` | Sixty-fourth note | Use the number |

Write `8C5`, not a duration after the pitch. The last duration stays in force
on a music line: `8C D E F` is four eighths. State the opening duration of each
new row. A continued row retains it across `|`; a separately addressed measure
starts its duration context again. Octave inference is separate and can carry
across that boundary.

Numeric and letter durations are both supported. Prefer a consistent spelling
within a file; the formatter can normalize to either. Mixing them is accepted,
but does not cancel inheritance or relax the meter.
`4G` and `qG` both mean a quarter-note G; `4G A B C` and `qG A B C`
both describe four quarters. The difference is spelling, not rhythm.

For example, `4G D E Eb | hD F r |` is overfull in 4/4: the first bar has
four quarters, but `hD` makes D, F, and the inline rest half-note values.
That second bar totals six quarter beats. If half D, quarter F, quarter rest
is intended, state the new quarter duration explicitly:

```scorescript
4G4 D E Eb | 2D 4F r
```

This is one possible correction, not a rule for guessing intended rhythms.
A literal `?` after the music is not a comment; use `//` for commentary.

```scorescript
8C5 D E F 4G G | 2C, 4r 8D E
```

## Dots and exact fractions

Put dots on the duration: `4.C5` is a dotted quarter and `4..C5` a
double-dotted quarter. `1/6C5` is exactly one sixth of a whole note.

`&` supplies the complementary shorter duration after a dotted value:
a dotted quarter plus `&D` gives a dotted quarter and an eighth, totaling a half note.
The complement does not replace the inherited duration: in `4.C5 &D E`,
E is another dotted quarter. State its duration when a different value is intended.

```scorescript
4.C5 &D 2E | 4..C 16D 2E
```

## Tuplets

Braces collect the notes in a tuplet. `{3: 8C D E}` is three eighths in the
time of two. Write an explicit normal count for another ratio, as in
`{5:3 8C D E F G}`: five eighths occupy three eighth-note units.

```scorescript
{3: 8C5 D E} 4F G A
```

The displayed tuplet bracket and rhythmic scaling refer to the same group.
Do not separately shorten the notes to compensate for the ratio.
An inherited eighth after the group is an ordinary eighth, not a tuplet eighth:
`{3: 8C D E} F` leaves F at one eighth. The example above explicitly switches
to quarters with `4F`.

## Rests and incomplete bars

`4r` is a quarter rest and `2r` a half rest. A lone bare `r` fills one whole
measure in the current meter. `r8` means eight measures of rest, while `8r`
means one eighth rest. The order changes the meaning.

| Source | Reading |
| --- | --- |
| `4C D E r` | Three quarter notes and a quarter rest |
| `2C D \| r` | Two half notes, then a full-bar rest |
| `r C D E` | Overfull: the opening bare rest claims a whole bar |
| `4r C D E` | A quarter rest, then three quarter notes |

Bare `r` does **not** mean “fill the remaining beats.” Inside a musical row
it inherits the established duration; standing alone in its bar it means a
full-bar rest, even after a bar of halves or eighths.

```scorescript
4C5 D 2r | r | r2 | 1C
```

A short ordinary bar is completed with rests and diagnosed. A pickup labeled
`m0:` stays short. An overfull bar is an error; a barline does not discard the
extra duration. Omitted ranges in a part can represent silence; see
[structure](structure.md).

## Grace notes

A slash before the duration marks a grace note, which takes no measured time
from the bar. Multiple grace notes may precede the main note.
The grace's duration can still change the inherited note value. State the
first main note's duration explicitly when it differs, as `4C` does here.

```scorescript
/8D5 4C D E F
```

The slash before a note is different from a slash after it: the latter is
a [glissando connector](connectors.md).