Need to escape space even in character class

Fixes #967

regexps.qmd

@@ -607,9 +607,9 @@ Spaces and new lines are ignored, as is everything after `#`.
 phone <- regex(r"(
   \(?     # optional opening parens
   (\d{3}) # area code
-  [) -]?  # optional closing parens, space, or dash
+  [)\ -]?  # optional closing parens, space, or dash
   (\d{3}) # another three numbers
-  [ -]?   # optional space or dash
+  [\ -]?   # optional space or dash
   (\d{3}) # three more numbers
   )", comments = TRUE)