== Why is this an issue?

Entries in the ASCII table below code 32 are known as control characters or non-printing characters. As they are not common in JavaScript strings, using these invisible characters in regular expressions is most likely a mistake.

[source,javascript,diff-id=1,diff-type=noncompliant]
----
const pattern1 = /\x1a/;             // Noncompliant: 1a (23 base 10) is less than 32
const pattern2 = new RegExp('\x1a'); // Noncompliant: 1a (23 base 10) is less than 32
----

Instead, one should only match printable characters in regular expressions.

[source,javascript,diff-id=1,diff-type=compliant]
----
const pattern1 = /\x20/;
const pattern2 = new RegExp('\x20');
----

== Resources

=== Documentation

* Wikipedia - https://en.wikipedia.org/wiki/ASCII[ASCII]
* Wikipedia - https://en.wikipedia.org/wiki/C0_and_C1_control_codes#C0_controls[C0 and C1 control codes]
* MDN web docs - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_expressions/Character_classes[Character classes]