https://github.com/jimhester/typeCheck
The typeCheck package automatically adds type checking code when types are annotated.
https://github.com/jimhester/typeCheck
Last synced: 3 months ago
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The typeCheck package automatically adds type checking code when types are annotated.
- Host: GitHub
- URL: https://github.com/jimhester/typeCheck
- Owner: jimhester
- License: other
- Created: 2016-09-12T20:03:14.000Z (about 9 years ago)
- Default Branch: master
- Last Pushed: 2020-07-15T10:56:38.000Z (over 5 years ago)
- Last Synced: 2025-04-03T08:12:06.026Z (7 months ago)
- Language: R
- Size: 37.1 KB
- Stars: 29
- Watchers: 5
- Forks: 2
- Open Issues: 5
-
Metadata Files:
- Readme: README.Rmd
- License: LICENSE
Awesome Lists containing this project
- jimsghstars - jimhester/typeCheck - The typeCheck package automatically adds type checking code when types are annotated. (R)
README
---
output: github_document
---
```{r, echo = FALSE}
knitr::opts_chunk$set(
collapse = TRUE,
comment = "#>",
fig.path = "README-"
)
```
## Type Check ##
[](https://travis-ci.org/jimhester/typeCheck)
[](https://codecov.io/github/jimhester/typeCheck?branch=master)
Type check allows use of [types](https://github.com/jimhester/types) to
automatically add checking code when types are annotated.
### Defining Types ###
`type_define()` is used to define a new type. The `check` argument specifies
a function used to verify the objects type. `type_check` adds the checks to a
specific function.
```{r error = TRUE}
type.numeric <- type_define(check = is.numeric)
f <- type_check(function(x = ? numeric) x)
f(1)
f("txt")
```
Types are defined as methods of the `type` generic. This means they follow the
same properties as normal S3 methods and can be exported and imported
to and from packages like all other functions.
The `error` argument is used to specify a custom error message for a type.
```{r error = TRUE}
type.numeric <- type_define(
check = is.numeric,
error = function(obj_name, obj_value, type) {
sprintf("%s: '%s' is not a number!", obj_name, obj_value)
})
f <- type_check(function(x = ? numeric) x)
f("txt")
```
### Packages ###
When writing a package adding a call to `typeCheck::type_check_package()`
anywhere outside a function will add type checks to all functions in the
package. Functions without type annotations are unaltered.
This means it is easy to add annotations in a stepwise process to existing
packages.
If you are using [roxygen2](https://github.com/klutometis/roxygen) You can use
the following `importFrom` statement (or use the equivalent `importFrom()` call directly
in the `NAMESPACE` file.)
```{r eval = FALSE}
f <- function(x = ? numeric) x
#' @importFrom typeCheck type type_define
typeCheck::type_check_package()
```