R: Special CRS values

wk_crs_inherit {wk} | R Documentation

## Special CRS values

### Description

The CRS handling in the wk package requires two sentinel CRS values. The first, `wk_crs_inherit()`, signals that the vector should inherit a CRS of another vector if combined. This is useful for empty, `NULL`, and/or zero-length geometries. The second, `wk_crs_auto()`, is used as the default argument of `crs` for constructors so that zero-length geometries are assigned a CRS of `wk_crs_inherit()` by default.

### Usage

    wk_crs_inherit()

    wk_crs_auto()

    wk_crs_auto_value(x, crs)

### Arguments

`x` | A raw input to a construuctor whose length and crs attributte is used to determine the default CRS returned by `wk_crs_auto()`.
`crs` | A value for the coordinate reference system supplied by the user.

### Examples

    wk_crs_auto_value(list(), wk_crs_auto())
    wk_crs_auto_value(list(), 1234)
    wk_crs_auto_value(list(NULL), wk_crs_auto())

[Package wk version 0.4.0 Index]