From 33bbf866ed3be72ccce955e5b2ee1bb99fa45e97 Mon Sep 17 00:00:00 2001
From: Al Dee <amyalicedee@gmail.com>
Date: Fri, 22 May 2020 13:34:23 +0100
Subject: Add the Option type.

---
 src/gleam/option.gleam | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 src/gleam/option.gleam

(limited to 'src')

diff --git a/src/gleam/option.gleam b/src/gleam/option.gleam
new file mode 100644
index 0000000..30bc1e2
--- /dev/null
+++ b/src/gleam/option.gleam
@@ -0,0 +1,38 @@
+/// Option represents a value that may be present or not. Some means the value is
+/// present, None means the value is not.
+///
+/// This is Gleam's alternative to having a value that could be Null, as is
+/// possible in some other languages.
+///
+pub type Option(a) {
+  Some(a)
+  None
+}
+
+/// Check whether the option is a Some value.
+///
+/// ## Examples
+///
+///    > is_some(Some(1))
+///    True
+///
+///    > is_some(None)
+///    False
+///
+pub fn is_some(option: Option(a)) -> Bool {
+  option != None
+}
+
+/// Check whether the option is a None value.
+///
+/// ## Examples
+///
+///    > is_none(Some(1))
+///    False
+///
+///    > is_none(None)
+///    True
+///
+pub fn is_none(option: Option(a)) -> Bool {
+  option == None
+}
-- 
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