JS pair module support

2 files changed, 113 insertions, 117 deletions

diff --git a/src/gleam/pair.gleam b/src/gleam/pair.gleam
index 246ce8c..6143ee9 100644
--- a/src/gleam/pair.gleam
+++ b/src/gleam/pair.gleam
@@ -1,63 +1,61 @@
-if erlang {
-  /// Returns the first element in a pair.
-  ///
-  /// ## Examples
-  ///
-  ///    > first(#(1, 2))
-  ///    1
-  ///
-  pub fn first(pair: #(a, b)) -> a {
-    let #(a, _) = pair
-    a
-  }
+/// Returns the first element in a pair.
+///
+/// ## Examples
+///
+///    > first(#(1, 2))
+///    1
+///
+pub fn first(pair: #(a, b)) -> a {
+  let #(a, _) = pair
+  a
+}
 
-  /// Returns the second element in a pair.
-  ///
-  /// ## Examples
-  ///
-  ///    > second(#(1, 2))
-  ///    2
-  ///
-  pub fn second(pair: #(a, b)) -> b {
-    let #(_, a) = pair
-    a
-  }
+/// Returns the second element in a pair.
+///
+/// ## Examples
+///
+///    > second(#(1, 2))
+///    2
+///
+pub fn second(pair: #(a, b)) -> b {
+  let #(_, a) = pair
+  a
+}
 
-  /// Returns a new pair with the elements swapped.
-  ///
-  /// ## Examples
-  ///
-  ///    > swap(#(1, 2))
-  ///    #(2, 1)
-  ///
-  pub fn swap(pair: #(a, b)) -> #(b, a) {
-    let #(a, b) = pair
-    #(b, a)
-  }
+/// Returns a new pair with the elements swapped.
+///
+/// ## Examples
+///
+///    > swap(#(1, 2))
+///    #(2, 1)
+///
+pub fn swap(pair: #(a, b)) -> #(b, a) {
+  let #(a, b) = pair
+  #(b, a)
+}
 
-  /// Returns a new pair with the first element having had `with` applied to
-  /// it.
-  ///
-  /// ## Examples
-  ///
-  ///    > #(1, 2) |> map_first(fn(n) { n * 2 })
-  ///    2
-  ///
-  pub fn map_first(of pair: #(a, b), with fun: fn(a) -> c) -> #(c, b) {
-    let #(a, b) = pair
-    #(fun(a), b)
-  }
+/// Returns a new pair with the first element having had `with` applied to
+/// it.
+///
+/// ## Examples
+///
+///    > #(1, 2) |> map_first(fn(n) { n * 2 })
+///    2
+///
+pub fn map_first(of pair: #(a, b), with fun: fn(a) -> c) -> #(c, b) {
+  let #(a, b) = pair
+  #(fun(a), b)
+}
 
-  /// Returns a new pair with the second element having had `with` applied to
-  /// it.
-  ///
-  /// ## Examples
-  ///
-  ///    > #(1, 2) |> map_second(fn(n) { n * 2 })
-  ///    4
-  ///
-  pub fn map_second(of pair: #(a, b), with fun: fn(b) -> c) -> #(a, c) {
-    let #(a, b) = pair
-    #(a, fun(b))
-  }
+/// Returns a new pair with the second element having had `with` applied to
+/// it.
+///
+/// ## Examples
+///
+///    > #(1, 2) |> map_second(fn(n) { n * 2 })
+///    4
+///
+pub fn map_second(of pair: #(a, b), with fun: fn(b) -> c) -> #(a, c) {
+  let #(a, b) = pair
+  #(a, fun(b))
 }
diff --git a/test/gleam/pair_test.gleam b/test/gleam/pair_test.gleam
index 891ce4a..1950929 100644
--- a/test/gleam/pair_test.gleam
+++ b/test/gleam/pair_test.gleam
@@ -1,60 +1,58 @@
-if erlang {
-  import gleam/should
-  import gleam/pair
-
-  pub fn first_test() {
-    #(1, 2)
-    |> pair.first
-    |> should.equal(1)
-
-    #("abc", [])
-    |> pair.first
-    |> should.equal("abc")
-  }
-
-  pub fn second_test() {
-    #(1, 2)
-    |> pair.second
-    |> should.equal(2)
-
-    #("abc", [])
-    |> pair.second
-    |> should.equal([])
-  }
-
-  pub fn swap_test() {
-    #(1, "2")
-    |> pair.swap
-    |> should.equal(#("2", 1))
-  }
-
-  pub fn map_first_test() {
-    let inc = fn(a) { a + 1 }
-    pair.map_first(#(1, 2), inc)
-    |> should.equal(#(2, 2))
-
-    pair.map_first(#(8, 2), inc)
-    |> should.equal(#(9, 2))
-
-    pair.map_first(#(0, -2), inc)
-    |> should.equal(#(1, -2))
-
-    pair.map_first(#(-10, 20), inc)
-    |> should.equal(#(-9, 20))
-  }
-
-  pub fn map_second_test() {
-    let dec = fn(a) { a - 1 }
-    pair.map_second(#(1, 2), dec)
-    |> should.equal(#(1, 1))
-
-    pair.map_second(#(8, 2), dec)
-    |> should.equal(#(8, 1))
-
-    pair.map_second(#(0, -2), dec)
-    |> should.equal(#(0, -3))
-
-    pair.map_second(#(-10, 20), dec)
-    |> should.equal(#(-10, 19))
-  }
+import gleam/should
+import gleam/pair
+
+pub fn first_test() {
+  #(1, 2)
+  |> pair.first
+  |> should.equal(1)
+
+  #("abc", [])
+  |> pair.first
+  |> should.equal("abc")
+}
+
+pub fn second_test() {
+  #(1, 2)
+  |> pair.second
+  |> should.equal(2)
+
+  #("abc", [])
+  |> pair.second
+  |> should.equal([])
+}
+
+pub fn swap_test() {
+  #(1, "2")
+  |> pair.swap
+  |> should.equal(#("2", 1))
+}
+
+pub fn map_first_test() {
+  let inc = fn(a) { a + 1 }
+  pair.map_first(#(1, 2), inc)
+  |> should.equal(#(2, 2))
+
+  pair.map_first(#(8, 2), inc)
+  |> should.equal(#(9, 2))
+
+  pair.map_first(#(0, -2), inc)
+  |> should.equal(#(1, -2))
+
+  pair.map_first(#(-10, 20), inc)
+  |> should.equal(#(-9, 20))
+}
+
+pub fn map_second_test() {
+  let dec = fn(a) { a - 1 }
+  pair.map_second(#(1, 2), dec)
+  |> should.equal(#(1, 1))
+
+  pair.map_second(#(8, 2), dec)
+  |> should.equal(#(8, 1))
+
+  pair.map_second(#(0, -2), dec)
+  |> should.equal(#(0, -3))
+
+  pair.map_second(#(-10, 20), dec)
+  |> should.equal(#(-10, 19))
 }