Adding en dash rule

.vale/fixtures/RedHat/EnDashes/.vale.ini

@@ -0,0 +1,5 @@
+; Vale configuration file to test the `EnDashes` rule
+StylesPath = ../../../styles
+MinAlertLevel = suggestion
+[*.adoc]
+RedHat.EnDashes = YES

.vale/fixtures/RedHat/EnDashes/testinvalid.adoc

@@ -0,0 +1,3 @@
+50 - 100 px
+50-100 px
+50 – 100 px

.vale/fixtures/RedHat/EnDashes/testvalid.adoc

@@ -0,0 +1,4 @@
+numbers 12–15
+pages 100–107
+X'41'–X'FE'
+September–December

.vale/styles/RedHat/EnDashes.yml

@@ -0,0 +1,11 @@
+---
+extends: substitution
+level: warning
+link: https://redhat-documentation.github.io/vale-at-red-hat/docs/main/reference-guide/endashes/
+message: "Use an en dash to show a range of numbers. Do not use a space before or after the en dash."
+nonword: true
+action:
+  name: replace
+swap:
+  (\d+)\s?-\s?(\d+): $1–$2
+  (\d+)\s–\s(\d+): $1–$2

modules/reference-guide/nav.adoc

@@ -9,6 +9,7 @@
 * xref:donotuseterms.adoc[]
 * xref:ellipses.adoc[]
 * xref:emdashes.adoc[]
+* xref:endashes.adoc[]
 * xref:headingpunctuation.adoc[]
 * xref:headings.adoc[]
 * xref:hyphens.adoc[]

modules/reference-guide/pages/endashes.adoc

@@ -0,0 +1,18 @@
+:navtitle: Endashes
+:keywords: reference, rule, endashes
+
+= En dashes
+
+Use an link:https://www.compart.com/en/unicode/U+2013[En dash] (`–`) to show a range of numbers.
+Do not use spaces before or after the En dash.
+
+[NOTE]
+====
+An link:https://www.compart.com/en/unicode/U+2014[Em dash] (`-`) is not the same as an En dash.
+The Em dash works like a comma, a colon, or parenthesis.
+====
+
+.Additional resources
+
+* link:{ibmsg-url-print}[{ibmsg-print} - En dashes, p.48]
+* link:{ibmsg-url}?topic=punctuation-dashes#showing-ranges-with-en-dashes[{ibmsg} - Showing ranges with en dashes]