Typeful reader API about libraries HOT 2 OPEN

data class CsvFile(val file: File)

/**
 * Returns the [CSV file][CsvFile] matching the given [path], or returns `null`
 * if no file was found from the `"resources"` and the
 * `"${user.home}/.kotools/csv"` folders.
 *
 * The `.csv` extension is **optional** in the [path].
 * For example, calling this function with `"folder/file.csv"` produces the same
 * output as calling it with `"folder/file"`.
 */
fun csvFileOrNull(path: NotBlankString): CsvFile? {
    val filePath: NotBlankString = path.takeIf { it.value.endsWith(".csv") }
        ?: NotBlankString("$path.csv")
    val file: File? = ClassLoader.getSystemResource(filePath.value)
        ?.let { File(it.path) }
        ?: System.getProperty("user.home")
            .let(::Path)
            .resolve(".kotools")
            .resolve("csv")
            .resolve(filePath.value)
            .takeIf { it.exists() }
            ?.toFile()
    return file?.let(::CsvFile)
}