sourceutils: Source Reference Utilities

Description

These functions extract information from source references.

Usage

getSrcFilename(x, full.names = FALSE, unique = TRUE)
getSrcDirectory(x, unique = TRUE)
getSrcref(x)
getSrcLocation(x, which = c("line", "column", "byte", "parse"),
               first = TRUE)

Arguments

An object (typically a function) containing source references.

full.names

Whether to include the full path in the filename result.

unique

Whether to list only unique filenames/directories.

which

Which part of a source reference to extract. Can be abbreviated.

first

Whether to show the first (or last) location of the object.

Value

getSrcFilename and getSrcDirectory return character vectors holding the filename/directory.

getSrcref returns a list of "srcref" objects or NULL if there are none.

getSrcLocation returns an integer vector of the requested type of locations.

Details

Each statement of a function will have its own source reference if the "keep.source" option is TRUE. These functions retrieve all of them.

The components are as follows:

line: The line number where the object starts or ends.
column: The column number where the object starts or ends.
byte: As for "column", but counting bytes, which may differ in case of multibyte characters.
parse: As for "line", but this ignores #line directives.

Examples

Run this code

fn <- function(x) {
  x + 1 # A comment, kept as part of the source
}			

# Show the temporary file directory
# where the example was saved

getSrcDirectory(fn)
getSrcLocation(fn, "line")