Functions for creating and checking lyrics objects.
lyrical(x)
as_lyrics(x, format = NULL)
is_lyrics(x)
lyrics_template(x, format = NULL)character or lyrics object. For lyrics_template(), an integer or
one of the classes noteworthy, noteinfo or music to derive the number
of timesteps from.
NULL or character, the timestep delimiter format, "space"
or "vector".
depends on the function
The lyrics class is a simple class for arranging lyrics text by timestep.
Its structure and behavior aligns with that of the classes noteworthy,
noteinfo and music.
lyrical() is a trivial function that returns a scalar logical result
essentially for any object that inherits from character, though this check
may become more specific in the future.
as_lyrics() can be used to coerce to the lyrics class. Coercion will fail
if the string is not lyrical. The lyrics class has its own print() and
summary() methods.
When format = NULL, the timestep delimiter format is inferred from the
lyrical string input.
# space-delimited lyrics; use periods for timesteps with no lyric
x <- "These are the ly- rics . . . to this song"
is_lyrics(x)
#> [1] FALSE
lyrical(x)
#> [1] TRUE
as_lyrics(x)
#> <Lyrics string>
#> Format: space-delimited time
#> Values: These are the ly- rics . . . to this song
# character vector; empty, period or NA for no lyric
x <- c("These", "are", "the", "ly-", "rics",
"", ".", NA, "to", "this", "song") #
as_lyrics(x)
#> <Lyrics string>
#> Format: vectorized time
#> Values: These are the ly- rics . . . to this song
# generate empty lyrics object from noteworthy, noteinfo or music object
notes <- as_noteworthy("c d e d c r*3 e g c'")
x <- lyrics_template(notes)
x
#> <Lyrics string>
#> Format: space-delimited time
#> Values: . . . . . . . . . . .
x[1:5] <- strsplit("These are the ly- rics", " ")[[1]]
x[9:11] <- c("to", "this", "song")
x
#> <Lyrics string>
#> Format: space-delimited time
#> Values: These are the ly- rics . . . to this song
summary(x)
#> <Lyrics string>
#> Timesteps: 11 (8 lyrics, 3 pauses)
#> Format: space-delimited time
#> Values: These are the ly- rics . . . to this song
attributes(x)
#> $steps
#> [1] 11
#>
#> $n_lyric
#> [1] 8
#>
#> $n_pause
#> [1] 3
#>
#> $format
#> [1] "space-delimited time"
#>
#> $class
#> [1] "lyrics" "character"
#>