Yuri

A type-safe URI builder for Kotlin. Work in progress.

tree

All usage examples are based on the following hypothetical file tree:

localhost ├── bin │ ├── sh │ └── sh.distrib | └── sh ├── etc │ ├── vim | └── script.sh └── usr ├── bin │ └── vim └── local └── bin └── sh

import

To work properly, Yuri needs a wildcard import:

kotlin import Y.*

usage

Yuri provides compile-time URI validation with a URI-like syntax.

```kotlin listOf( // Compiles! Y.uri(localhost), Y.uri(localhost /bin), Y.uri(localhost /bin/sh), Y.uri(localhost /bin/sh.distrib), Y.uri(localhost /bin/sh.distrib/sh), Y.uri(localhost /etc), Y.uri(localhost /etc/vim), Y.uri(localhost /etc/script.sh), Y.uri(localhost /usr), Y.uri(localhost /usr/bin/vim), Y.uri(localhost /usr/local), Y.uri(localhost /usr/local/bin), Y.uri(localhost /usr/local/bin/sh),

Y.uri(projectDir),
Y.uri(projectDir /gradle),
Y.uri(projectDir /gradlew),
Y.uri(projectDir /settings_dot_gradle),
Y.uri(projectDir /src/main),
Y.uri(projectDir /src/main/kotlin)

// Does not compile!
// ,Y.uri(localhost /local)
// ,Y.uri(localhost /bin/vim)
// ,Y.uri(localhost /sh)
// ,Y.uri(localhost /bin/local)
// ,Y.uri(localhost /etc/local)
// ,Y.uri(localhost /etc/sh)
// ,Y.uri(localhost /etc/script)
// ,Y.uri(localhost /usr/local/sh)
// ,Y.uri(localhost /usr/local/bin/sh.distrib)
// ,Y.uri(projectDir /test)
// ,Y.uri(projectDir /compileKotlin)
// ,Y.uri(projectDir /kotlin)
// ,Y.uri(projectDir /production/classes/main)

).forEach { println("$it") } ```

search

You can perform Kleene-star prefix searches using Kotlin's spread-operator:

```kotlin listOf( // Compiles! *bin, *sh, *vim, *bin/sh, *bin/sh.distrib, *etc/vim, *usr/bin, *sh.distrib, *sh.distrib/sh, *script.sh, *etc/script.sh

// Does not compile!
// , *etc/bin
// , *etc/sh
// , *local/usr
// , *sh/distrib
// , *sh/sh

).forEach { path -> println("*$path -> ${Y.uris(path)}") } ```

batch

Yuri provides an extension function for batch ops over multiple files:

kotlin Y.uris(*sh) { println(it) } Y.uris(*sh) { it.createNewFile() } Y.uris(*sh) { it.appendText("Hello Yuri") } Y.uris(*sh) { it.setReadOnly() }

examples

To reproduce the example code above, run the following command from the project directory:

./gradlew run

generate

To generate the file tree, run the following command from the consumer directory:

../gradlew genSources [-Path=<absolute path to perform file tree scan>]

Unless -Path is specified, Yuri will scan the project directory. Code generation is provided by Kotlin Poet.

how?

See:

• Y.kt, for DSL and type checking
• Yuri.kt, for code generation

why?

• Because Strings are error prone (FileNotFoundException, NoSuchFileException...)

• Many filesystems can be scanned quickly and do not change

• To stress test Kotlin's type checker

• Real time automatic code generation is getting better

• Abusing operator overloading is fun! Learn how a DSL works

• Might come in handy for scripting and build automation

• Static resource discovery, e.g. webpage crawling, IP address scanning

• Projects freqently need to reference absolute or project-local resources