Remaining float functions for JS

3 files changed, 187 insertions, 157 deletions

diff --git a/src/gleam/float.gleam b/src/gleam/float.gleam
index 1191ac1..0ad788c 100644
--- a/src/gleam/float.gleam
+++ b/src/gleam/float.gleam
@@ -170,59 +170,83 @@ if javascript {
     "../gleam_stdlib.js" "round"
 }
 
+/// Returns the value as an int, truncating all decimal digits.
+///
+/// ## Examples
+///
+///    > truncate(2.4343434847383438)
+///    2
+///
+pub fn truncate(float: Float) -> Int {
+  do_truncate(float)
+}
+
 if erlang {
-  /// Returns the value as an int, truncating all decimal digits.
-  ///
-  /// ## Examples
-  ///
-  ///    > truncate(2.4343434847383438)
-  ///    2
-  ///
-  pub external fn truncate(Float) -> Int =
-    "erlang" "trunc"
+  external fn do_truncate(Float) -> Int =
+    "math" "trunc"
+}
 
-  /// Returns the absolute value of the input as a float.
-  ///
-  /// ## Examples
-  ///
-  ///    > absolute_value(-12.5)
-  ///    12.5
-  ///
-  ///    > absolute_value(10.2)
-  ///    10.2
-  ///
-  pub external fn absolute_value(Float) -> Float =
-    "erlang" "abs"
+if javascript {
+  external fn do_truncate(Float) -> Int =
+    "../gleam_stdlib.js" "truncate"
+}
 
-  /// Returns the results of the base being raised to the power of the
-  /// exponent, as a float.
-  ///
-  /// ## Examples
-  ///
-  ///    > power(2.0, 2.0)
-  ///    4.0
-  ///
-  ///    > power(8.0, 1.5)
-  ///    64.0
-  ///
-  pub external fn power(base: Float, exponent: Float) -> Float =
+/// Returns the absolute value of the input as a float.
+///
+/// ## Examples
+///
+///    > absolute_value(-12.5)
+///    12.5
+///
+///    > absolute_value(10.2)
+///    10.2
+///
+pub fn absolute_value(float: Float) -> Float {
+  case float >=. 0. {
+    True -> float
+    _ -> 0. -. float
+  }
+}
+
+/// Returns the results of the base being raised to the power of the
+/// exponent, as a float.
+///
+/// ## Examples
+///
+///    > power(2.0, 2.0)
+///    4.0
+///
+///    > power(8.0, 1.5)
+///    64.0
+///
+pub fn power(base: Float, exponent: Float) -> Float {
+  do_power(base, exponent)
+}
+
+if erlang {
+  external fn do_power(Float, Float) -> Float =
     "math" "pow"
+}
 
-  /// Returns the square root of the input as a float.
-  ///
-  /// ## Examples
-  ///
-  ///    > square_root(4.0)
-  ///    Ok(2.0)
-  ///
-  ///    > square_root(-16.0)
-  ///    Error(Nil)
-  ///
-  pub fn square_root(number: Float) -> Result(Float, Nil) {
-    case number <. 0.0 {
-      True -> Error(Nil)
-      False -> Ok(power(number, 0.5))
-    }
+if javascript {
+  external fn do_power(Float, Float) -> Float =
+    "../gleam_stdlib.js" "power"
+}
+
+/// Returns the square root of the input as a float.
+///
+/// ## Examples
+///
+///    > square_root(4.0)
+///    Ok(2.0)
+///
+///    > square_root(-16.0)
+///    Error(Nil)
+///
+pub fn square_root(number: Float) -> Result(Float, Nil) {
+  case number <. 0.0 {
+    True -> Error(Nil)
+    False -> Ok(power(number, 0.5))
   }
 }
 
diff --git a/src/gleam_stdlib.js b/src/gleam_stdlib.js
index 8b2f131..479b8a9 100644
--- a/src/gleam_stdlib.js
+++ b/src/gleam_stdlib.js
@@ -236,3 +236,11 @@ export function floor(float) {
 export function round(float) {
   return Math.round(float);
 }
+
+export function truncate(float) {
+  return Math.trunc(float);
+}
+
+export function power(base, exponent) {
+  return Math.pow(base, exponent);
+}
diff --git a/test/gleam/float_test.gleam b/test/gleam/float_test.gleam
index a449f79..c7107d9 100644
--- a/test/gleam/float_test.gleam
+++ b/test/gleam/float_test.gleam
@@ -131,154 +131,152 @@ pub fn round_test() {
   |> should.equal(-8)
 }
 
-if erlang {
-  pub fn truncate_test() {
-    8.1
-    |> float.truncate
-    |> should.equal(8)
+pub fn truncate_test() {
+  8.1
+  |> float.truncate
+  |> should.equal(8)
 
-    8.4
-    |> float.truncate
-    |> should.equal(8)
+  8.4
+  |> float.truncate
+  |> should.equal(8)
 
-    8.499
-    |> float.truncate
-    |> should.equal(8)
+  8.499
+  |> float.truncate
+  |> should.equal(8)
 
-    8.5
-    |> float.truncate
-    |> should.equal(8)
+  8.5
+  |> float.truncate
+  |> should.equal(8)
 
-    -8.1
-    |> float.truncate
-    |> should.equal(-8)
+  -8.1
+  |> float.truncate
+  |> should.equal(-8)
 
-    -7.5
-    |> float.truncate
-    |> should.equal(-7)
-  }
+  -7.5
+  |> float.truncate
+  |> should.equal(-7)
+}
 
-  pub fn min_test() {
-    float.min(0., 0.)
-    |> should.equal(0.)
+pub fn min_test() {
+  float.min(0., 0.)
+  |> should.equal(0.)
 
-    float.min(0.3, 1.5)
-    |> should.equal(0.3)
+  float.min(0.3, 1.5)
+  |> should.equal(0.3)
 
-    float.min(1., 0.)
-    |> should.equal(0.)
+  float.min(1., 0.)
+  |> should.equal(0.)
 
-    float.min(-1.7, 2.5)
-    |> should.equal(-1.7)
+  float.min(-1.7, 2.5)
+  |> should.equal(-1.7)
 
-    float.min(-2.2, -2.2)
-    |> should.equal(-2.2)
+  float.min(-2.2, -2.2)
+  |> should.equal(-2.2)
 
-    float.min(-1., -1.)
-    |> should.equal(-1.)
+  float.min(-1., -1.)
+  |> should.equal(-1.)
 
-    float.min(-1.1, -1.)
-    |> should.equal(-1.1)
-  }
+  float.min(-1.1, -1.)
+  |> should.equal(-1.1)
+}
 
-  pub fn max_test() {
-    float.max(0., 0.)
-    |> should.equal(0.)
+pub fn max_test() {
+  float.max(0., 0.)
+  |> should.equal(0.)
 
-    float.max(0.3, 1.5)
-    |> should.equal(1.5)
+  float.max(0.3, 1.5)
+  |> should.equal(1.5)
 
-    float.max(1., 0.)
-    |> should.equal(1.)
+  float.max(1., 0.)
+  |> should.equal(1.)
 
-    float.max(-1.7, 2.5)
-    |> should.equal(2.5)
+  float.max(-1.7, 2.5)
+  |> should.equal(2.5)
 
-    float.max(-2.2, -2.2)
-    |> should.equal(-2.2)
+  float.max(-2.2, -2.2)
+  |> should.equal(-2.2)
 
-    float.max(-1., -1.)
-    |> should.equal(-1.)
+  float.max(-1., -1.)
+  |> should.equal(-1.)
 
-    float.max(-1.1, -1.)
-    |> should.equal(-1.)
-  }
+  float.max(-1.1, -1.)
+  |> should.equal(-1.)
+}
 
-  pub fn absolute_value_test() {
-    float.absolute_value(-1.0)
-    |> should.equal(1.0)
+pub fn absolute_value_test() {
+  float.absolute_value(-1.0)
+  |> should.equal(1.0)
 
-    float.absolute_value(-20.6)
-    |> should.equal(20.6)
+  float.absolute_value(-20.6)
+  |> should.equal(20.6)
 
-    float.absolute_value(0.0)
-    |> should.equal(0.0)
+  float.absolute_value(0.0)
+  |> should.equal(0.0)
 
-    float.absolute_value(1.0)
-    |> should.equal(1.0)
+  float.absolute_value(1.0)
+  |> should.equal(1.0)
 
-    float.absolute_value(25.2)
-    |> should.equal(25.2)
-  }
+  float.absolute_value(25.2)
+  |> should.equal(25.2)
+}
 
-  pub fn power_test() {
-    float.power(2.0, 2.0)
-    |> should.equal(4.0)
+pub fn power_test() {
+  float.power(2.0, 2.0)
+  |> should.equal(4.0)
 
-    float.power(-5.0, 3.0)
-    |> should.equal(-125.0)
+  float.power(-5.0, 3.0)
+  |> should.equal(-125.0)
 
-    float.power(10.5, 0.0)
-    |> should.equal(1.0)
+  float.power(10.5, 0.0)
+  |> should.equal(1.0)
 
-    float.power(16.0, 0.5)
-    |> should.equal(4.0)
+  float.power(16.0, 0.5)
+  |> should.equal(4.0)
 
-    float.power(2.0, -1.0)
-    |> should.equal(0.5)
-  }
+  float.power(2.0, -1.0)
+  |> should.equal(0.5)
+}
 
-  pub fn square_root_test() {
-    float.square_root(4.0)
-    |> should.equal(Ok(2.0))
+pub fn square_root_test() {
+  float.square_root(4.0)
+  |> should.equal(Ok(2.0))
 
-    float.square_root(16.0)
-    |> should.equal(Ok(4.0))
+  float.square_root(16.0)
+  |> should.equal(Ok(4.0))
 
-    float.square_root(0.0)
-    |> should.equal(Ok(0.0))
+  float.square_root(0.0)
+  |> should.equal(Ok(0.0))
 
-    float.square_root(-4.0)
-    |> should.equal(Error(Nil))
-  }
+  float.square_root(-4.0)
+  |> should.equal(Error(Nil))
+}
 
-  pub fn negate_test() {
-    float.negate(-1.)
-    |> should.equal(1.)
+pub fn negate_test() {
+  float.negate(-1.)
+  |> should.equal(1.)
 
-    float.negate(2.)
-    |> should.equal(-2.)
+  float.negate(2.)
+  |> should.equal(-2.)
 
-    float.negate(0.)
-    |> should.equal(0.)
-  }
+  float.negate(0.)
+  |> should.equal(0.)
+}
 
-  pub fn sum_test() {
-    float.sum([])
-    |> should.equal(0.0)
+pub fn sum_test() {
+  float.sum([])
+  |> should.equal(0.0)
 
-    float.sum([1.0, 2.2, 3.3])
-    |> should.equal(6.5)
-  }
+  float.sum([1.0, 2.2, 3.3])
+  |> should.equal(6.5)
+}
 
-  pub fn product_test() {
-    float.product([])
-    |> should.equal(0.)
+pub fn product_test() {
+  float.product([])
+  |> should.equal(0.)
 
-    float.product([4.])
-    |> should.equal(4.)
+  float.product([4.])
+  |> should.equal(4.)
 
-    float.product([2.5, 3.2, 4.2])
-    |> should.equal(33.6)
-  }
+  float.product([2.5, 3.2, 4.2])
+  |> should.equal(33.6)
 }