robot-simulator

robot-simulator/.exercism/config.json

@@ -0,0 +1,22 @@
+{
+  "authors": [
+    "jiegillet"
+  ],
+  "files": {
+    "solution": [
+      "src/robot_simulator.gleam"
+    ],
+    "test": [
+      "test/robot_simulator_test.gleam"
+    ],
+    "example": [
+      ".meta/example.gleam"
+    ],
+    "invalidator": [
+      "gleam.toml",
+      "manifest.toml"
+    ]
+  },
+  "blurb": "Write a robot simulator.",
+  "source": "Inspired by an interview question at a famous company."
+}

robot-simulator/.exercism/metadata.json

@@ -0,0 +1 @@
+{"track":"gleam","exercise":"robot-simulator","id":"09f398f0a29f4e6d9e8c542184b210a7","url":"https://exercism.org/tracks/gleam/exercises/robot-simulator","handle":"fw353qwgs","is_requester":true,"auto_approve":false}

robot-simulator/.gitignore

@@ -0,0 +1,4 @@
+*.beam
+*.ez
+build
+erl_crash.dump

robot-simulator/HELP.md

@@ -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/robot_simulator.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.

robot-simulator/README.md

@@ -0,0 +1,40 @@
+# Robot Simulator
+
+Welcome to Robot Simulator on Exercism's Gleam Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Write a robot simulator.
+
+A robot factory's test facility needs a program to verify robot movements.
+
+The robots have three possible movements:
+
+- turn right
+- turn left
+- advance
+
+Robots are placed on a hypothetical infinite grid, facing a particular direction (north, east, south, or west) at a set of {x,y} coordinates,
+e.g., {3,8}, with coordinates increasing to the north and east.
+
+The robot then receives a number of instructions, at which point the testing facility verifies the robot's new position, and in which direction it is pointing.
+
+- The letter-string "RAALAL" means:
+  - Turn right
+  - Advance twice
+  - Turn left
+  - Advance once
+  - Turn left yet again
+- Say a robot starts at {7, 3} facing north.
+  Then running this stream of instructions should leave it at {9, 4} facing west.
+
+## Source
+
+### Created by
+
+- @jiegillet
+
+### Based on
+
+Inspired by an interview question at a famous company.

robot-simulator/gleam.toml

@@ -0,0 +1,14 @@
+name = "robot_simulator"
+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"

robot-simulator/manifest.toml

@@ -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" }

robot-simulator/src/robot_simulator.gleam

@@ -0,0 +1,84 @@
+import gleam/io
+import gleam/string
+
+pub type Robot {
+  Robot(direction: Direction, position: Position)
+}
+
+pub type Direction {
+  North
+  East
+  South
+  West
+}
+
+pub type Turn {
+  Turn(left: Direction, right: Direction)
+}
+
+pub type Position {
+  Position(x: Int, y: Int)
+}
+
+pub fn create(direction: Direction, position: Position) -> Robot {
+  Robot(direction:, position:)
+}
+
+pub fn move(
+  direction: Direction,
+  position: Position,
+  instructions: String,
+) -> Robot {
+  string.split(instructions, "")
+  |> move_loop(#(direction, position))
+  |> fn(dp) { Robot(dp.0, dp.1) }
+}
+
+fn move_loop(
+  instructions: List(String),
+  dp: #(Direction, Position),
+) -> #(Direction, Position) {
+  io.debug(instructions)
+  io.debug(dp)
+  case instructions {
+    [] -> dp
+    [head, ..tail] -> handle_instruction(head, dp) |> move_loop(tail, _)
+  }
+}
+
+fn handle_instruction(
+  instruction: String,
+  dp: #(Direction, Position),
+) -> #(Direction, Position) {
+  case instruction {
+    "L" | "R" -> #(turn(dp.0, instruction), dp.1)
+    "A" -> advance(dp)
+    _ -> dp
+  }
+}
+
+fn turn(facing: Direction, to: String) -> Direction {
+  let turn = case facing {
+    North -> Turn(left: West, right: East)
+    East -> Turn(left: North, right: South)
+    South -> Turn(left: East, right: West)
+    West -> Turn(left: South, right: North)
+  }
+
+  case to {
+    "L" -> turn.left
+    "R" -> turn.right
+    _ -> facing
+  }
+}
+
+fn advance(dp: #(Direction, Position)) -> #(Direction, Position) {
+  let #(facing, p) = dp
+  case facing {
+    North -> Position(..p, y: p.y + 1)
+    East -> Position(..p, x: p.x + 1)
+    South -> Position(..p, y: p.y - 1)
+    West -> Position(..p, x: p.x - 1)
+  }
+  |> fn(updated_position: Position) { #(facing, updated_position) }
+}

robot-simulator/test/robot_simulator_test.gleam

@@ -0,0 +1,97 @@
+import exercism/should
+import exercism/test_runner
+import robot_simulator.{East, North, Position, Robot, South, West}
+
+pub fn main() {
+  test_runner.main()
+}
+
+pub fn create_robot_at_origin_facing_north_test() {
+  robot_simulator.create(North, Position(x: 0, y: 0))
+  |> should.equal(Robot(North, Position(x: 0, y: 0)))
+}
+
+pub fn create_robot_at_negative_position_facing_south_test() {
+  robot_simulator.create(South, Position(x: -1, y: -1))
+  |> should.equal(Robot(South, Position(x: -1, y: -1)))
+}
+
+pub fn rotating_clockwise_changes_north_to_east_test() {
+  robot_simulator.move(North, Position(x: 0, y: 0), "R")
+  |> should.equal(Robot(East, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_clockwise_changes_east_to_south_test() {
+  robot_simulator.move(East, Position(x: 0, y: 0), "R")
+  |> should.equal(Robot(South, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_clockwise_changes_south_to_west_test() {
+  robot_simulator.move(South, Position(x: 0, y: 0), "R")
+  |> should.equal(Robot(West, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_clockwise_changes_west_to_north_test() {
+  robot_simulator.move(West, Position(x: 0, y: 0), "R")
+  |> should.equal(Robot(North, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_counter_clockwise_changes_north_to_west_test() {
+  robot_simulator.move(North, Position(x: 0, y: 0), "L")
+  |> should.equal(Robot(West, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_counter_clockwise_changes_west_to_south_test() {
+  robot_simulator.move(West, Position(x: 0, y: 0), "L")
+  |> should.equal(Robot(South, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_counter_clockwise_changes_south_to_east_test() {
+  robot_simulator.move(South, Position(x: 0, y: 0), "L")
+  |> should.equal(Robot(East, Position(x: 0, y: 0)))
+}
+
+pub fn rotating_counter_clockwise_changes_east_to_north_test() {
+  robot_simulator.move(East, Position(x: 0, y: 0), "L")
+  |> should.equal(Robot(North, Position(x: 0, y: 0)))
+}
+
+pub fn moving_forward_one_facing_north_increments_y_test() {
+  robot_simulator.move(North, Position(x: 0, y: 0), "A")
+  |> should.equal(Robot(North, Position(x: 0, y: 1)))
+}
+
+pub fn moving_forward_one_facing_south_decrements_y_test() {
+  robot_simulator.move(South, Position(x: 0, y: 0), "A")
+  |> should.equal(Robot(South, Position(x: 0, y: -1)))
+}
+
+pub fn moving_forward_one_facing_east_increments_x_test() {
+  robot_simulator.move(East, Position(x: 0, y: 0), "A")
+  |> should.equal(Robot(East, Position(x: 1, y: 0)))
+}
+
+pub fn moving_forward_one_facing_west_decrements_x_test() {
+  robot_simulator.move(West, Position(x: 0, y: 0), "A")
+  |> should.equal(Robot(West, Position(x: -1, y: 0)))
+}
+
+pub fn follow_series_of_instructions_moving_east_and_north_from_readme_test() {
+  robot_simulator.move(North, Position(x: 7, y: 3), "RAALAL")
+  |> should.equal(Robot(West, Position(x: 9, y: 4)))
+}
+
+pub fn follow_series_of_instructions_moving_west_and_north_test() {
+  robot_simulator.move(North, Position(x: 0, y: 0), "LAAARALA")
+  |> should.equal(Robot(West, Position(x: -4, y: 1)))
+}
+
+pub fn follow_series_of_instructions_moving_west_and_south_test() {
+  robot_simulator.move(East, Position(x: 2, y: -7), "RRAAAAALA")
+  |> should.equal(Robot(South, Position(x: -3, y: -8)))
+}
+
+pub fn follow_series_of_instructions_moving_east_and_north_test() {
+  robot_simulator.move(South, Position(x: 8, y: 4), "LAAARRRALLLL")
+  |> should.equal(Robot(North, Position(x: 11, y: 5)))
+}