mark (version 0.8.1)

note: Append a note to an object

Description

An alternative to the base::comment().

Usage

note(x) <- value
set_note(x, value)
note(x)

Value

• note<-, set_note() will return x (with the "note" attribute assigned)

• note() will retrieve the "note" attribute

Arguments

x

An object

value

The note to attach; if NULL will remove the note and the class noted from the object.

Details

When the note is assigned to an object a new class will be added, note, so that a print function can call an S3 method. The print for this can be adjusted for it's width by using the option mark.note.width which defaults to the option width when not set.

The type of object assigned to the note is not restricted, so user beware of odd prints or additional features added to the notes fun.

When assigning a note (with note<-, and its alias set_note()) the noted class is added to the object. This allows the print.noted class to be dispatched and for the note to be printed every time the object is called/printed and the next print method used. However, it will not be called when not interactive()

Examples

x <- c("x", "k", "c", "d")
comment(x) <- "This is just a comment"
comment(x)

# Comment is intentionally hidden
x
note(x) <- "Just some random letters"
note(x)

# Note is now present every time
x

# Assigning `NULL` will remove note (and class)
note(x) <- NULL
note(x) # NULL
x       # No more note