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| Author | SHA1 | Date | |
|---|---|---|---|
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760f5ef4a6 | ||
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0d5036c5c4 |
21
erlang-extraction/.exercism/config.json
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21
erlang-extraction/.exercism/config.json
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@@ -0,0 +1,21 @@
|
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{
|
||||
"authors": [
|
||||
"lpil"
|
||||
],
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||||
"files": {
|
||||
"solution": [
|
||||
"src/erlang_extraction.gleam"
|
||||
],
|
||||
"test": [
|
||||
"test/erlang_extraction_test.gleam"
|
||||
],
|
||||
"exemplar": [
|
||||
".meta/example.gleam"
|
||||
],
|
||||
"invalidator": [
|
||||
"gleam.toml",
|
||||
"manifest.toml"
|
||||
]
|
||||
},
|
||||
"blurb": "Learn about external types and functions by using an Erlang library"
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}
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1
erlang-extraction/.exercism/metadata.json
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1
erlang-extraction/.exercism/metadata.json
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||||
{"track":"gleam","exercise":"erlang-extraction","id":"567185dac6004b25b6b5bc1eb51faa91","url":"https://exercism.org/tracks/gleam/exercises/erlang-extraction","handle":"fw353qwgs","is_requester":true,"auto_approve":false}
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||||
4
erlang-extraction/.gitignore
vendored
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4
erlang-extraction/.gitignore
vendored
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@@ -0,0 +1,4 @@
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||||
*.beam
|
||||
*.ez
|
||||
build
|
||||
erl_crash.dump
|
||||
32
erlang-extraction/HELP.md
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32
erlang-extraction/HELP.md
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@@ -0,0 +1,32 @@
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||||
# Help
|
||||
|
||||
## Running the tests
|
||||
|
||||
To run the tests, run the command `gleam test` from within the exercise directory.
|
||||
|
||||
## Submitting your solution
|
||||
|
||||
You can submit your solution using the `exercism submit src/erlang_extraction.gleam` command.
|
||||
This command will upload your solution to the Exercism website and print the solution page's URL.
|
||||
|
||||
It's possible to submit an incomplete solution which allows you to:
|
||||
|
||||
- See how others have completed the exercise
|
||||
- Request help from a mentor
|
||||
|
||||
## Need to get help?
|
||||
|
||||
If you'd like help solving the exercise, check the following pages:
|
||||
|
||||
- The [Gleam track's documentation](https://exercism.org/docs/tracks/gleam)
|
||||
- The [Gleam track's programming category on the forum](https://forum.exercism.org/c/programming/gleam)
|
||||
- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5)
|
||||
- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
|
||||
|
||||
Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
|
||||
|
||||
To get help if you're having trouble, you can use one of the following resources:
|
||||
|
||||
- [gleam.run](https://gleam.run/documentation/) is the gleam official documentation.
|
||||
- [Discord](https://discord.gg/Fm8Pwmy) is the discord channel.
|
||||
- [StackOverflow](https://stackoverflow.com/questions/tagged/gleam) can be used to search for your problem and see if it has been answered already. You can also ask and answer questions.
|
||||
23
erlang-extraction/HINTS.md
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23
erlang-extraction/HINTS.md
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# Hints
|
||||
|
||||
## 1. Define the `GbTree` external type
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|
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- External types can be defined using the `pub type TypeName(a, b, c)` syntax.
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||||
|
||||
## 2. Define the `new_gb_tree` function
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||||
|
||||
- External functions can be defined using the `@external(erlang, "module", "function")` syntax.
|
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- The function should use the `gb_trees:empty/0`.
|
||||
|
||||
## 3. Define the `insert` function
|
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|
||||
- Check the `gb_trees:insert/3` documentation to confirm the correct order of arguments.
|
||||
- The external function can be a private function that is called by the `insert` function in order to change the order of the arguments.
|
||||
- The function should use the `gb_trees:insert/3`.
|
||||
|
||||
## 4. Define the `delete` function
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||||
|
||||
- Check the `gb_trees:delete_any/2` documentation to confirm the correct order of arguments.
|
||||
- The external function can be a private function that is called by the `delete` function in order to change the order of the arguments.
|
||||
- The function should use the `gb_trees:delete_any/2`.
|
||||
- The `gb_trees:delete/2` function will crash if the key is not found, so it should not be used.
|
||||
108
erlang-extraction/README.md
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108
erlang-extraction/README.md
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||||
# Erlang Extraction
|
||||
|
||||
Welcome to Erlang Extraction on Exercism's Gleam Track.
|
||||
If you need help running the tests or submitting your code, check out `HELP.md`.
|
||||
If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :)
|
||||
|
||||
## Introduction
|
||||
|
||||
## External Functions
|
||||
|
||||
Gleam can run on the Erlang virtual machine (BEAM), or on JavaScript runtimes. There are many other languages that use these runtimes, and it is often useful to be able to call code written in these languages from Gleam.
|
||||
|
||||
Gleam's _external functions_ feature permits functions in other languages to be imported into Gleam and called with no runtime overhead.
|
||||
|
||||
If your Gleam project runs on the Erlang virtual machine and you wish to call the `reverse` function from the Erlang `lists` module you can do it by adding the `@external` attribute to a Gleam function head like this:
|
||||
|
||||
```gleam
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@external(erlang, "lists", "reverse")
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||||
pub fn reverse_list(x: List(a)) -> List(a)
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||||
```
|
||||
|
||||
This can then be called as a normal Gleam function:
|
||||
|
||||
```gleam
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||||
let reversed = reverse_list([1, 2, 3])
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||||
// -> [3, 2, 1]
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||||
```
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||||
|
||||
If you attempt to compile this code for JavaScript runtimes it will fail with an error message as there is no implementation for JavaScript. Another implementation can be specified for JavaScript runtimes like this:
|
||||
|
||||
```gleam
|
||||
@external(erlang, "lists", "reverse")
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||||
@external(javascript, "./my_module.mjs", "reverse")
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||||
pub fn reverse_list(x: List(a)) -> List(a)
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||||
```
|
||||
|
||||
It is also possible to write a Gleam implementation that will be used when there is no external implementation for the current compile target:
|
||||
|
||||
```gleam
|
||||
@external(erlang, "lists", "reverse")
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||||
pub fn reverse_list(x: List(a)) -> List(a) {
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tail_recursive_reverse(x, [])
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||||
}
|
||||
|
||||
fn tail_recursive_reverse(list, reversed) {
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||||
case list {
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||||
[] -> reversed
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[x, ..xs] -> tail_recursive_reverse(xs, [x, ..reversed])
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||||
}
|
||||
}
|
||||
```
|
||||
|
||||
## External Types
|
||||
|
||||
External types can be used to refer to data types defined in other languages, such as Erlang or JavaScript.
|
||||
|
||||
To define an external type declare a type but do not provide any constructors. This can then be used in the same way as any other type.
|
||||
|
||||
```gleam
|
||||
pub type OrderedDictionary(element)
|
||||
```
|
||||
|
||||
## Instructions
|
||||
|
||||
Tadhg has found the perfect Erlang library to help with his project. Being an older Erlang library it is using the `gb_trees` module rather than the newer `maps` module for storing data.
|
||||
|
||||
Help out Tadgh by creating external types and functions for working with `gb_trees` in Gleam.
|
||||
|
||||
## 1. Define the `GbTree` external type
|
||||
|
||||
The `GbTree` type should have two type parameters, a key type and a value type. It should have no constructors, making it an external type.
|
||||
|
||||
## 2. Define the `new_gb_tree` function
|
||||
|
||||
The `new_gb_tree` function should take no arguments and return an empty `GbTree`.
|
||||
|
||||
It should use the [`gb_trees:empty/0` function][empty] from the Erlang standard library.
|
||||
|
||||
## 3. Define the `insert` function
|
||||
|
||||
The `insert` function should take a `GbTree` and a key and value to insert into the tree. It should return a new `GbTree` with the key and value inserted.
|
||||
|
||||
The function should take three arguments:
|
||||
1. The `GbTree` to insert into.
|
||||
2. The key to insert.
|
||||
3. The value to insert.
|
||||
|
||||
It should use the [`gb_trees:insert/3` function][insert] from the Erlang standard library.
|
||||
|
||||
## 4. Define the `delete` function
|
||||
|
||||
The `delete` function should take a `GbTree` and a key to delete from the tree. It should return a new `GbTree` with the key and value deleted.
|
||||
|
||||
The function should take two arguments:
|
||||
1. The `GbTree` to delete from.
|
||||
2. The key to delete.
|
||||
|
||||
It should use the [`gb_trees:delete_any/2` function][delete_any] from the Erlang standard library.
|
||||
|
||||
[empty]: https://www.erlang.org/doc/apps/stdlib/gb_trees.html#empty/0
|
||||
[insert]: https://www.erlang.org/doc/apps/stdlib/gb_trees.html#insert/3
|
||||
[delete_any]: https://www.erlang.org/doc/apps/stdlib/gb_trees.html#delete_any/2
|
||||
|
||||
## Source
|
||||
|
||||
### Created by
|
||||
|
||||
- @lpil
|
||||
14
erlang-extraction/gleam.toml
Normal file
14
erlang-extraction/gleam.toml
Normal file
@@ -0,0 +1,14 @@
|
||||
name = "erlang_extraction"
|
||||
version = "0.1.0"
|
||||
|
||||
[dependencies]
|
||||
gleam_otp = "~> 0.7 or ~> 1.0"
|
||||
gleam_stdlib = ">= 0.54.0 or ~> 1.0"
|
||||
simplifile = "~> 1.0"
|
||||
gleam_erlang = ">= 0.25.0 and < 1.0.0"
|
||||
gleam_yielder = ">= 1.1.0 and < 2.0.0"
|
||||
gleam_regexp = ">= 1.1.0 and < 2.0.0"
|
||||
gleam_deque = ">= 1.0.0 and < 2.0.0"
|
||||
|
||||
[dev-dependencies]
|
||||
exercism_test_runner = "~> 1.9"
|
||||
31
erlang-extraction/manifest.toml
Normal file
31
erlang-extraction/manifest.toml
Normal file
@@ -0,0 +1,31 @@
|
||||
# This file was generated by Gleam
|
||||
# You typically do not need to edit this file
|
||||
|
||||
packages = [
|
||||
{ name = "argv", version = "1.0.2", build_tools = ["gleam"], requirements = [], otp_app = "argv", source = "hex", outer_checksum = "BA1FF0929525DEBA1CE67256E5ADF77A7CDDFE729E3E3F57A5BDCAA031DED09D" },
|
||||
{ name = "exercism_test_runner", version = "1.9.0", build_tools = ["gleam"], requirements = ["argv", "gap", "glance", "gleam_community_ansi", "gleam_erlang", "gleam_json", "gleam_stdlib", "simplifile"], otp_app = "exercism_test_runner", source = "hex", outer_checksum = "0B17BB25F2FF1E60266467C24FE0CA04005410306AA05E9A4B41B1852D72865C" },
|
||||
{ name = "filepath", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "filepath", source = "hex", outer_checksum = "67A6D15FB39EEB69DD31F8C145BB5A421790581BD6AA14B33D64D5A55DBD6587" },
|
||||
{ name = "gap", version = "1.1.3", build_tools = ["gleam"], requirements = ["gleam_community_ansi", "gleam_stdlib"], otp_app = "gap", source = "hex", outer_checksum = "6EF5E3B523FDFBC317E9EA28D5163EE04744A97C007106F90207569789612291" },
|
||||
{ name = "glance", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "glexer"], otp_app = "glance", source = "hex", outer_checksum = "E155BA1A787FD11827048355021C0390D2FE9A518485526F631A9D472858CC6D" },
|
||||
{ name = "gleam_community_ansi", version = "1.4.3", build_tools = ["gleam"], requirements = ["gleam_community_colour", "gleam_regexp", "gleam_stdlib"], otp_app = "gleam_community_ansi", source = "hex", outer_checksum = "8A62AE9CC6EA65BEA630D95016D6C07E4F9973565FA3D0DE68DC4200D8E0DD27" },
|
||||
{ name = "gleam_community_colour", version = "2.0.0", build_tools = ["gleam"], requirements = ["gleam_json", "gleam_stdlib"], otp_app = "gleam_community_colour", source = "hex", outer_checksum = "FDD6AC62C6EC8506C005949A4FCEF032038191D5EAAEC3C9A203CD53AE956ACA" },
|
||||
{ name = "gleam_deque", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_deque", source = "hex", outer_checksum = "64D77068931338CF0D0CB5D37522C3E3CCA7CB7D6C5BACB41648B519CC0133C7" },
|
||||
{ name = "gleam_erlang", version = "0.34.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "0C38F2A128BAA0CEF17C3000BD2097EB80634E239CE31A86400C4416A5D0FDCC" },
|
||||
{ name = "gleam_json", version = "2.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_json", source = "hex", outer_checksum = "C55C5C2B318533A8072D221C5E06E5A75711C129E420DD1CE463342106012E5D" },
|
||||
{ name = "gleam_otp", version = "0.16.1", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "50DA1539FC8E8FA09924EB36A67A2BBB0AD6B27BCDED5A7EF627057CF69D035E" },
|
||||
{ name = "gleam_regexp", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_regexp", source = "hex", outer_checksum = "7F5E0C0BBEB3C58E57C9CB05FA9002F970C85AD4A63BA1E55CBCB35C15809179" },
|
||||
{ name = "gleam_stdlib", version = "0.55.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "32D8F4AE03771516950047813A9E359249BD9FBA5C33463FDB7B953D6F8E896B" },
|
||||
{ name = "gleam_yielder", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_yielder", source = "hex", outer_checksum = "8E4E4ECFA7982859F430C57F549200C7749823C106759F4A19A78AEA6687717A" },
|
||||
{ name = "glexer", version = "2.2.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "glexer", source = "hex", outer_checksum = "5C235CBDF4DA5203AD5EAB1D6D8B456ED8162C5424FE2309CFFB7EF438B7C269" },
|
||||
{ name = "simplifile", version = "1.7.0", build_tools = ["gleam"], requirements = ["filepath", "gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "1D5DFA3A2F9319EC85825F6ED88B8E449F381B0D55A62F5E61424E748E7DDEB0" },
|
||||
]
|
||||
|
||||
[requirements]
|
||||
exercism_test_runner = { version = "~> 1.9" }
|
||||
gleam_deque = { version = ">= 1.0.0 and < 2.0.0" }
|
||||
gleam_erlang = { version = ">= 0.25.0 and < 1.0.0" }
|
||||
gleam_otp = { version = "~> 0.7 or ~> 1.0" }
|
||||
gleam_regexp = { version = ">= 1.1.0 and < 2.0.0" }
|
||||
gleam_stdlib = { version = ">= 0.54.0 or ~> 1.0" }
|
||||
gleam_yielder = { version = ">= 1.1.0 and < 2.0.0" }
|
||||
simplifile = { version = "~> 1.0" }
|
||||
20
erlang-extraction/src/erlang_extraction.gleam
Normal file
20
erlang-extraction/src/erlang_extraction.gleam
Normal file
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|
||||
// Please define the GbTree type
|
||||
|
||||
pub type GbTree(k, v)
|
||||
|
||||
@external(erlang, "gb_trees", "empty")
|
||||
pub fn new_gb_tree() -> GbTree(k, v)
|
||||
|
||||
pub fn insert(tree: GbTree(k, v), key: k, value: v) -> GbTree(k, v) {
|
||||
gb_trees_insert(key, value, tree)
|
||||
}
|
||||
|
||||
@external(erlang, "gb_trees", "insert")
|
||||
fn gb_trees_insert(key: k, value: v, tree: GbTree(k, v)) -> GbTree(k, v)
|
||||
|
||||
pub fn delete(tree: GbTree(k, v), key: k) -> GbTree(k, v) {
|
||||
gb_trees_delete_any(key, tree)
|
||||
}
|
||||
|
||||
@external(erlang, "gb_trees", "delete_any")
|
||||
fn gb_trees_delete_any(key: k, tree: GbTree(k, v)) -> GbTree(k, v)
|
||||
54
erlang-extraction/test/erlang_extraction_test.gleam
Normal file
54
erlang-extraction/test/erlang_extraction_test.gleam
Normal file
@@ -0,0 +1,54 @@
|
||||
import erlang_extraction.{type GbTree}
|
||||
import exercism/should
|
||||
import exercism/test_runner
|
||||
|
||||
pub fn main() {
|
||||
test_runner.main()
|
||||
}
|
||||
|
||||
@external(erlang, "gb_trees", "to_list")
|
||||
fn to_list(tree: GbTree(k, v)) -> List(#(k, v))
|
||||
|
||||
pub fn new_gb_tree_test() {
|
||||
erlang_extraction.new_gb_tree()
|
||||
|> to_list
|
||||
|> should.equal([])
|
||||
}
|
||||
|
||||
pub fn insert_int_string_test() {
|
||||
erlang_extraction.new_gb_tree()
|
||||
|> erlang_extraction.insert(1, "one")
|
||||
|> erlang_extraction.insert(2, "two")
|
||||
|> erlang_extraction.insert(3, "three")
|
||||
|> to_list
|
||||
|> should.equal([#(1, "one"), #(2, "two"), #(3, "three")])
|
||||
}
|
||||
|
||||
pub fn insert_string_int_test() {
|
||||
erlang_extraction.new_gb_tree()
|
||||
|> erlang_extraction.insert("one", 1)
|
||||
|> erlang_extraction.insert("two", 2)
|
||||
|> erlang_extraction.insert("three", 3)
|
||||
|> to_list
|
||||
|> should.equal([#("one", 1), #("three", 3), #("two", 2)])
|
||||
}
|
||||
|
||||
pub fn delete_test() {
|
||||
erlang_extraction.new_gb_tree()
|
||||
|> erlang_extraction.insert(1, "one")
|
||||
|> erlang_extraction.insert(2, "two")
|
||||
|> erlang_extraction.insert(3, "three")
|
||||
|> erlang_extraction.delete(2)
|
||||
|> to_list
|
||||
|> should.equal([#(1, "one"), #(3, "three")])
|
||||
}
|
||||
|
||||
pub fn delete_non_existing_test() {
|
||||
erlang_extraction.new_gb_tree()
|
||||
|> erlang_extraction.insert(1, "one")
|
||||
|> erlang_extraction.insert(2, "two")
|
||||
|> erlang_extraction.insert(3, "three")
|
||||
|> erlang_extraction.delete(4)
|
||||
|> to_list
|
||||
|> should.equal([#(1, "one"), #(2, "two"), #(3, "three")])
|
||||
}
|
||||
21
expert-experiments/.exercism/config.json
Normal file
21
expert-experiments/.exercism/config.json
Normal file
@@ -0,0 +1,21 @@
|
||||
{
|
||||
"authors": [
|
||||
"lpil"
|
||||
],
|
||||
"files": {
|
||||
"solution": [
|
||||
"src/expert_experiments.gleam"
|
||||
],
|
||||
"test": [
|
||||
"test/expert_experiments_test.gleam"
|
||||
],
|
||||
"exemplar": [
|
||||
".meta/example.gleam"
|
||||
],
|
||||
"invalidator": [
|
||||
"gleam.toml",
|
||||
"manifest.toml"
|
||||
]
|
||||
},
|
||||
"blurb": "Learn about use expressions by conducting some experiments"
|
||||
}
|
||||
1
expert-experiments/.exercism/metadata.json
Normal file
1
expert-experiments/.exercism/metadata.json
Normal file
@@ -0,0 +1 @@
|
||||
{"track":"gleam","exercise":"expert-experiments","id":"4f12bf49f75c4ebaba7dc8a949bd874b","url":"https://exercism.org/tracks/gleam/exercises/expert-experiments","handle":"fw353qwgs","is_requester":true,"auto_approve":false}
|
||||
4
expert-experiments/.gitignore
vendored
Normal file
4
expert-experiments/.gitignore
vendored
Normal file
@@ -0,0 +1,4 @@
|
||||
*.beam
|
||||
*.ez
|
||||
build
|
||||
erl_crash.dump
|
||||
32
expert-experiments/HELP.md
Normal file
32
expert-experiments/HELP.md
Normal file
@@ -0,0 +1,32 @@
|
||||
# Help
|
||||
|
||||
## Running the tests
|
||||
|
||||
To run the tests, run the command `gleam test` from within the exercise directory.
|
||||
|
||||
## Submitting your solution
|
||||
|
||||
You can submit your solution using the `exercism submit src/expert_experiments.gleam` command.
|
||||
This command will upload your solution to the Exercism website and print the solution page's URL.
|
||||
|
||||
It's possible to submit an incomplete solution which allows you to:
|
||||
|
||||
- See how others have completed the exercise
|
||||
- Request help from a mentor
|
||||
|
||||
## Need to get help?
|
||||
|
||||
If you'd like help solving the exercise, check the following pages:
|
||||
|
||||
- The [Gleam track's documentation](https://exercism.org/docs/tracks/gleam)
|
||||
- The [Gleam track's programming category on the forum](https://forum.exercism.org/c/programming/gleam)
|
||||
- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5)
|
||||
- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
|
||||
|
||||
Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
|
||||
|
||||
To get help if you're having trouble, you can use one of the following resources:
|
||||
|
||||
- [gleam.run](https://gleam.run/documentation/) is the gleam official documentation.
|
||||
- [Discord](https://discord.gg/Fm8Pwmy) is the discord channel.
|
||||
- [StackOverflow](https://stackoverflow.com/questions/tagged/gleam) can be used to search for your problem and see if it has been answered already. You can also ask and answer questions.
|
||||
15
expert-experiments/HINTS.md
Normal file
15
expert-experiments/HINTS.md
Normal file
@@ -0,0 +1,15 @@
|
||||
# Hints
|
||||
|
||||
## 1. Define the `with_retry` function
|
||||
|
||||
- A `case` expression can be used to pattern match on a result.
|
||||
|
||||
## 2. Define the `record_timing` function
|
||||
|
||||
- The `time_logger` function should be called even if the `experiment` function returns an `Error` value.
|
||||
|
||||
## 3. Define the `run_experiment` function
|
||||
|
||||
- The [`result.try` function][result-try] can be used in a `use` expression to stop if a result is an `Error` value.
|
||||
|
||||
[result-try]: https://hexdocs.pm/gleam_stdlib/gleam/result.html#try
|
||||
149
expert-experiments/README.md
Normal file
149
expert-experiments/README.md
Normal file
@@ -0,0 +1,149 @@
|
||||
# Expert Experiments
|
||||
|
||||
Welcome to Expert Experiments on Exercism's Gleam Track.
|
||||
If you need help running the tests or submitting your code, check out `HELP.md`.
|
||||
If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :)
|
||||
|
||||
## Introduction
|
||||
|
||||
## Use Expressions
|
||||
|
||||
In Gleam it is common to write and use higher order functions, that is functions that take other functions as arguments. Sometimes when using many higher order functions at once the code can become difficult to read, with many layers of indentation.
|
||||
|
||||
For example, here is a function that calls several functions that return `Result(Int, Nil)`, and sums the values if all four are successful.
|
||||
|
||||
```gleam
|
||||
import gleam/result
|
||||
|
||||
pub fn main() -> Result(Int, Nil) {
|
||||
result.try(function1(), fn(a) {
|
||||
result.try(function2(), fn(b) {
|
||||
result.try(function3(), fn(c) {
|
||||
result.try(function4(), fn(d) {
|
||||
Ok(a + b + c + d)
|
||||
})
|
||||
})
|
||||
})
|
||||
})
|
||||
}
|
||||
```
|
||||
|
||||
Gleam's `use` expressions allow us to write this code without the indentation, often making it easier to read.
|
||||
|
||||
```gleam
|
||||
import gleam/result
|
||||
|
||||
pub fn main() -> Result(Int, Nil) {
|
||||
use a <- result.try(function1())
|
||||
use b <- result.try(function2())
|
||||
use c <- result.try(function3())
|
||||
use d <- result.try(function4())
|
||||
Ok(a + b + c + d)
|
||||
}
|
||||
```
|
||||
|
||||
A `use` expression collects all the following statements in the block and passes it as a callback function as the final argument to the function call. The variables between the `use` keyword and the `<-` symbol are the names of the arguments that will be passed to the callback function.
|
||||
|
||||
```gleam
|
||||
// This use expression
|
||||
use a <- function(1, 2)
|
||||
io.println("Hello!")
|
||||
a
|
||||
|
||||
// Is equivalent to this normal function call
|
||||
function(1, 2, fn(a) {
|
||||
io.println("Hello!")
|
||||
a
|
||||
})
|
||||
```
|
||||
|
||||
The callback function can take any number of arguments, or none at all.
|
||||
|
||||
```gleam
|
||||
use a, b, c, d <- call_4_function()
|
||||
|
||||
use <- call_0_function()
|
||||
```
|
||||
|
||||
There are no special requirements to create a function that can be called with a `use` expression, other than taking a callback function as the final argument.
|
||||
|
||||
```gleam
|
||||
pub fn call_twice(function: fn() -> t) -> #(t, t) {
|
||||
let first = function()
|
||||
let second = function()
|
||||
#(first, second)
|
||||
}
|
||||
```
|
||||
|
||||
Gleam's `use` expressions are a very powerful feature that can be applied to lots of problems, but when overused they can make code difficult to read. It is generally preferred to use the normal function call syntax and only reach for `use` expressions when they make the code easier to read.
|
||||
|
||||
## Instructions
|
||||
|
||||
Daphne has been working on a system to run and record the results of her experiments. Some of the code has become a bit verbose and repetitive, so she's asked you to write some `use` expressions to help clean it up.
|
||||
|
||||
## 1. Define the `with_retry` function
|
||||
|
||||
Sometimes experiments can fail due to a one-off mistake, so if an experiment fails Daphne wants to retry it again to see if it works the second time.
|
||||
|
||||
Define the `with_retry` function that takes a result returning function as an argument.
|
||||
|
||||
If the function returns an `Ok` value then `with_retry` should return that value.
|
||||
|
||||
If the function returns an `Error` value then `with_retry` should call the function again and return the result of that call.
|
||||
|
||||
Daphne will use the function like this:
|
||||
|
||||
```gleam
|
||||
pub fn main() {
|
||||
use <- with_retry
|
||||
// Perform the experiment here
|
||||
}
|
||||
```
|
||||
|
||||
## 2. Define the `record_timing` function
|
||||
|
||||
Daphne records how long each experiment takes to run by calling a time logging function before and after each experiment.
|
||||
|
||||
Define the `record_timing` function that takes two arguments:
|
||||
- A time logging function which takes no arguments and returns `Nil`.
|
||||
- An experiment function which takes no arguments and returns a result.
|
||||
|
||||
`record_timing` should call the time logging function, then call the experiment function, then call the time logging function again, and finally return the result of the experiment function.
|
||||
|
||||
Daphne will use the function like this:
|
||||
|
||||
```gleam
|
||||
pub fn main() {
|
||||
use <- record_timing(time_logger)
|
||||
// Perform the experiment here
|
||||
}
|
||||
```
|
||||
|
||||
## 3. Define the `run_experiment` function
|
||||
|
||||
Experiments are made up of three phases. The setup, the action, and the recording. All three phases return results, and each phase needs the successful result of the previous phase to run.
|
||||
|
||||
Define the `run_experiment` function that takes four arguments:
|
||||
- The name of the experiment as a `String`.
|
||||
- A setup function which takes no arguments and returns a result.
|
||||
- An action function which takes the `Ok` value of the setup function as an argument and returns a result.
|
||||
- A recording function which takes the `Ok` value of the setup and action functions as arguments and returns a result.
|
||||
|
||||
If all three functions succeed then `run_experiment` should return `Ok(#(experiment_name, recording_data))`.
|
||||
|
||||
If any of the functions return an `Error` value then `run_experiment` should return that value.
|
||||
|
||||
Daphne will use the function like this:
|
||||
|
||||
```gleam
|
||||
pub fn main() {
|
||||
use setup_data, action_data <- run_experiment("Test 1", setup, action)
|
||||
// Record the results here
|
||||
}
|
||||
```
|
||||
|
||||
## Source
|
||||
|
||||
### Created by
|
||||
|
||||
- @lpil
|
||||
14
expert-experiments/gleam.toml
Normal file
14
expert-experiments/gleam.toml
Normal file
@@ -0,0 +1,14 @@
|
||||
name = "expert_experiments"
|
||||
version = "0.1.0"
|
||||
|
||||
[dependencies]
|
||||
gleam_otp = "~> 0.7 or ~> 1.0"
|
||||
gleam_stdlib = ">= 0.54.0 or ~> 1.0"
|
||||
simplifile = "~> 1.0"
|
||||
gleam_erlang = ">= 0.25.0 and < 1.0.0"
|
||||
gleam_yielder = ">= 1.1.0 and < 2.0.0"
|
||||
gleam_regexp = ">= 1.1.0 and < 2.0.0"
|
||||
gleam_deque = ">= 1.0.0 and < 2.0.0"
|
||||
|
||||
[dev-dependencies]
|
||||
exercism_test_runner = "~> 1.9"
|
||||
31
expert-experiments/manifest.toml
Normal file
31
expert-experiments/manifest.toml
Normal file
@@ -0,0 +1,31 @@
|
||||
# This file was generated by Gleam
|
||||
# You typically do not need to edit this file
|
||||
|
||||
packages = [
|
||||
{ name = "argv", version = "1.0.2", build_tools = ["gleam"], requirements = [], otp_app = "argv", source = "hex", outer_checksum = "BA1FF0929525DEBA1CE67256E5ADF77A7CDDFE729E3E3F57A5BDCAA031DED09D" },
|
||||
{ name = "exercism_test_runner", version = "1.9.0", build_tools = ["gleam"], requirements = ["argv", "gap", "glance", "gleam_community_ansi", "gleam_erlang", "gleam_json", "gleam_stdlib", "simplifile"], otp_app = "exercism_test_runner", source = "hex", outer_checksum = "0B17BB25F2FF1E60266467C24FE0CA04005410306AA05E9A4B41B1852D72865C" },
|
||||
{ name = "filepath", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "filepath", source = "hex", outer_checksum = "67A6D15FB39EEB69DD31F8C145BB5A421790581BD6AA14B33D64D5A55DBD6587" },
|
||||
{ name = "gap", version = "1.1.3", build_tools = ["gleam"], requirements = ["gleam_community_ansi", "gleam_stdlib"], otp_app = "gap", source = "hex", outer_checksum = "6EF5E3B523FDFBC317E9EA28D5163EE04744A97C007106F90207569789612291" },
|
||||
{ name = "glance", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "glexer"], otp_app = "glance", source = "hex", outer_checksum = "E155BA1A787FD11827048355021C0390D2FE9A518485526F631A9D472858CC6D" },
|
||||
{ name = "gleam_community_ansi", version = "1.4.3", build_tools = ["gleam"], requirements = ["gleam_community_colour", "gleam_regexp", "gleam_stdlib"], otp_app = "gleam_community_ansi", source = "hex", outer_checksum = "8A62AE9CC6EA65BEA630D95016D6C07E4F9973565FA3D0DE68DC4200D8E0DD27" },
|
||||
{ name = "gleam_community_colour", version = "2.0.0", build_tools = ["gleam"], requirements = ["gleam_json", "gleam_stdlib"], otp_app = "gleam_community_colour", source = "hex", outer_checksum = "FDD6AC62C6EC8506C005949A4FCEF032038191D5EAAEC3C9A203CD53AE956ACA" },
|
||||
{ name = "gleam_deque", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_deque", source = "hex", outer_checksum = "64D77068931338CF0D0CB5D37522C3E3CCA7CB7D6C5BACB41648B519CC0133C7" },
|
||||
{ name = "gleam_erlang", version = "0.34.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "0C38F2A128BAA0CEF17C3000BD2097EB80634E239CE31A86400C4416A5D0FDCC" },
|
||||
{ name = "gleam_json", version = "2.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_json", source = "hex", outer_checksum = "C55C5C2B318533A8072D221C5E06E5A75711C129E420DD1CE463342106012E5D" },
|
||||
{ name = "gleam_otp", version = "0.16.1", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "50DA1539FC8E8FA09924EB36A67A2BBB0AD6B27BCDED5A7EF627057CF69D035E" },
|
||||
{ name = "gleam_regexp", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_regexp", source = "hex", outer_checksum = "7F5E0C0BBEB3C58E57C9CB05FA9002F970C85AD4A63BA1E55CBCB35C15809179" },
|
||||
{ name = "gleam_stdlib", version = "0.55.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "32D8F4AE03771516950047813A9E359249BD9FBA5C33463FDB7B953D6F8E896B" },
|
||||
{ name = "gleam_yielder", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_yielder", source = "hex", outer_checksum = "8E4E4ECFA7982859F430C57F549200C7749823C106759F4A19A78AEA6687717A" },
|
||||
{ name = "glexer", version = "2.2.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "glexer", source = "hex", outer_checksum = "5C235CBDF4DA5203AD5EAB1D6D8B456ED8162C5424FE2309CFFB7EF438B7C269" },
|
||||
{ name = "simplifile", version = "1.7.0", build_tools = ["gleam"], requirements = ["filepath", "gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "1D5DFA3A2F9319EC85825F6ED88B8E449F381B0D55A62F5E61424E748E7DDEB0" },
|
||||
]
|
||||
|
||||
[requirements]
|
||||
exercism_test_runner = { version = "~> 1.9" }
|
||||
gleam_deque = { version = ">= 1.0.0 and < 2.0.0" }
|
||||
gleam_erlang = { version = ">= 0.25.0 and < 1.0.0" }
|
||||
gleam_otp = { version = "~> 0.7 or ~> 1.0" }
|
||||
gleam_regexp = { version = ">= 1.1.0 and < 2.0.0" }
|
||||
gleam_stdlib = { version = ">= 0.54.0 or ~> 1.0" }
|
||||
gleam_yielder = { version = ">= 1.1.0 and < 2.0.0" }
|
||||
simplifile = { version = "~> 1.0" }
|
||||
31
expert-experiments/src/expert_experiments.gleam
Normal file
31
expert-experiments/src/expert_experiments.gleam
Normal file
@@ -0,0 +1,31 @@
|
||||
import gleam/result
|
||||
|
||||
pub fn with_retry(experiment: fn() -> Result(t, e)) -> Result(t, e) {
|
||||
case experiment() {
|
||||
Error(_) -> experiment()
|
||||
Ok(result) -> Ok(result)
|
||||
}
|
||||
}
|
||||
|
||||
pub fn record_timing(
|
||||
time_logger: fn() -> Nil,
|
||||
experiment: fn() -> Result(t, e),
|
||||
) -> Result(t, e) {
|
||||
time_logger()
|
||||
let result = experiment()
|
||||
time_logger()
|
||||
|
||||
result
|
||||
}
|
||||
|
||||
pub fn run_experiment(
|
||||
name: String,
|
||||
setup: fn() -> Result(t, e),
|
||||
action: fn(t) -> Result(u, e),
|
||||
record: fn(t, u) -> Result(v, e),
|
||||
) -> Result(#(String, v), e) {
|
||||
use setup_result <- result.try(setup())
|
||||
use action_result <- result.try(action(setup_result))
|
||||
use record_result <- result.try(record(setup_result, action_result))
|
||||
Ok(#(name, record_result))
|
||||
}
|
||||
143
expert-experiments/test/expert_experiments_test.gleam
Normal file
143
expert-experiments/test/expert_experiments_test.gleam
Normal file
@@ -0,0 +1,143 @@
|
||||
import exercism/should
|
||||
import exercism/test_runner
|
||||
import expert_experiments
|
||||
import gleam/erlang/process
|
||||
import gleam/list
|
||||
|
||||
pub fn main() {
|
||||
test_runner.main()
|
||||
}
|
||||
|
||||
fn mutable_yielder(elements: List(t)) -> fn() -> t {
|
||||
let subject = process.new_subject()
|
||||
list.each(elements, fn(element) { process.send(subject, element) })
|
||||
fn() {
|
||||
case process.receive(subject, 0) {
|
||||
Ok(element) -> element
|
||||
Error(_) -> panic as "Callback called too many times"
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn logger() -> #(fn(String) -> Nil, fn() -> List(String)) {
|
||||
let subject = process.new_subject()
|
||||
let writer = fn(message) { process.send(subject, message) }
|
||||
let reader = fn() { read_all(subject, []) }
|
||||
#(writer, reader)
|
||||
}
|
||||
|
||||
fn read_all(
|
||||
subject: process.Subject(String),
|
||||
read: List(String),
|
||||
) -> List(String) {
|
||||
case process.receive(subject, 0) {
|
||||
Ok(message) -> read_all(subject, [message, ..read])
|
||||
Error(_) -> list.reverse(read)
|
||||
}
|
||||
}
|
||||
|
||||
pub fn with_retry_pass_test() {
|
||||
let function = mutable_yielder([Ok("First"), Error("Second")])
|
||||
{
|
||||
use <- expert_experiments.with_retry
|
||||
function()
|
||||
}
|
||||
|> should.equal(Ok("First"))
|
||||
}
|
||||
|
||||
pub fn with_retry_fail_fail_test() {
|
||||
let function = mutable_yielder([Error("First"), Error("Second")])
|
||||
{
|
||||
use <- expert_experiments.with_retry
|
||||
function()
|
||||
}
|
||||
|> should.equal(Error("Second"))
|
||||
}
|
||||
|
||||
pub fn with_retry_fail_pass_test() {
|
||||
let function = mutable_yielder([Error("First"), Ok("Second")])
|
||||
{
|
||||
use <- expert_experiments.with_retry
|
||||
function()
|
||||
}
|
||||
|> should.equal(Ok("Second"))
|
||||
}
|
||||
|
||||
pub fn record_timing_pass_test() {
|
||||
let #(writer, reader) = logger()
|
||||
{
|
||||
use <- expert_experiments.record_timing(fn() { writer("timer") })
|
||||
writer("experiment")
|
||||
Ok(0)
|
||||
}
|
||||
|> should.equal(Ok(0))
|
||||
|
||||
reader()
|
||||
|> should.equal(["timer", "experiment", "timer"])
|
||||
}
|
||||
|
||||
pub fn record_timing_fail_test() {
|
||||
let #(writer, reader) = logger()
|
||||
{
|
||||
use <- expert_experiments.record_timing(fn() { writer("timer") })
|
||||
writer("experiment")
|
||||
Error(Nil)
|
||||
}
|
||||
|> should.equal(Error(Nil))
|
||||
|
||||
reader()
|
||||
|> should.equal(["timer", "experiment", "timer"])
|
||||
}
|
||||
|
||||
pub fn run_experiment_fail_test() {
|
||||
{
|
||||
let setup = fn() { Error("Setup failed") }
|
||||
let action = fn(_) { panic as "Should not run action" }
|
||||
use _, _ <- expert_experiments.run_experiment("Experiment 1", setup, action)
|
||||
panic as "Should not run record"
|
||||
}
|
||||
|> should.equal(Error("Setup failed"))
|
||||
}
|
||||
|
||||
pub fn run_experiment_pass_fail_test() {
|
||||
{
|
||||
let setup = fn() { Ok(1) }
|
||||
let action = fn(x) {
|
||||
should.equal(x, 1)
|
||||
Error("Action failed")
|
||||
}
|
||||
use _, _ <- expert_experiments.run_experiment("Experiment 1", setup, action)
|
||||
panic as "Should not run record"
|
||||
}
|
||||
|> should.equal(Error("Action failed"))
|
||||
}
|
||||
|
||||
pub fn run_experiment_pass_pass_fail_test() {
|
||||
{
|
||||
let setup = fn() { Ok(1) }
|
||||
let action = fn(x) {
|
||||
should.equal(x, 1)
|
||||
Ok("2")
|
||||
}
|
||||
use x, y <- expert_experiments.run_experiment("Experiment 1", setup, action)
|
||||
should.equal(x, 1)
|
||||
should.equal(y, "2")
|
||||
Error("Record failed")
|
||||
}
|
||||
|> should.equal(Error("Record failed"))
|
||||
}
|
||||
|
||||
pub fn run_experiment_pass_pass_pass_test() {
|
||||
{
|
||||
let setup = fn() { Ok(1) }
|
||||
let action = fn(x) {
|
||||
should.equal(x, 1)
|
||||
Ok("2")
|
||||
}
|
||||
use x, y <- expert_experiments.run_experiment("Experiment 1", setup, action)
|
||||
should.equal(x, 1)
|
||||
should.equal(y, "2")
|
||||
Ok("Success!")
|
||||
}
|
||||
|> should.equal(Ok(#("Experiment 1", "Success!")))
|
||||
}
|
||||
Reference in New Issue
Block a user