update

crystal/examples/tuples/named_tuple_with_non_alnum_fields.cr

@@ -0,0 +1,12 @@
+macro t(name)
+  print "%s %s\n" % {typeof({{name}}), {{name}}}
+end
+
+h = {a: 1, "a b-23": 2}
+t h
+h.each {|x, y|
+  t x
+  t y
+}
+
+

crystal/examples/tuples/optional_field.cr

@@ -0,0 +1,25 @@
+require "json"
+
+alias Person = NamedTuple(
+  name: String,
+  email: String?,
+)
+
+p1_str = %[{"name": "Foo", "email": "[email protected]"}]
+p1 = Person.from_json(p1_str)
+p p1
+
+
+p2_str = %[{"name": "Bar"}]
+p2 = Person.from_json(p2_str)
+# Unhandled exception: Missing json attribute: email
+p p2
+
+p3_str = %[{"name": "Bar", "email": null}]
+p3 = Person.from_json(p3_str)
+p p3
+
+# {name: "Foo", email: "[email protected]"}
+# {name: "Bar", email: nil}
+# {name: "Bar", email: nil}
+

crystal/tuples.md

@@ -21,3 +21,13 @@
 
 ![](examples/tuples/named_tuple_fields.cr)
 
+## Named Tuple with non-alphanumeric fields
+{id: named-tuple-with-non-alphanumeric-fields}
+
+![](examples/tuples/named_tuple_with_non_alnum_fields.cr)
+
+## Named Tuple with optional field
+{id: named-tuple-with-optional-field}
+
+![](examples/tuples/optional_field.cr)
+