Don't swallow space after boring prefixes

guide/src/format/config.md

@@ -275,16 +275,15 @@ mdBook will then test the regex on each line and follow this pattern:
 
 Here is the pattern generated for a boring prefix (the `{}` in replaced with the prefix string):
 ```re
-^(\s*)(?P<escape>\\)?{} ?(.*)$
+^(\s*)(?P<escape>\\)?{}(.*)$
 ```
 Breaking it down, we have
 - `^(\s*)`  
   Match the indentation, and put it in a group to preserve it in the output.
 - `(?P<escape>\\)?`  
   If we find a backslash this group will match and trigger the escape mechanism.
-- `{} ?`  
-  Match the prefix and optionally the space after it. Note how this isn't in a group, meaning it 
-  won't be included in the final line.
+- `{}`  
+  Match the prefix. Note how this isn't in a group, meaning it won't be included in the final line.
 - `(.*)$`  
   Match the rest of the line, and put it in a group to preserve it in the output.
 

guide/src/format/mdbook.md

@@ -48,8 +48,8 @@ the prefix can be escaped using a backslash. With the python example above, this
         print(a, end=' ')
         a, b = b, a+b
     print()
-    ~ # hide me!
-    \~ # leave me be!
+    ~# hide me!
+    \~# leave me be!
 ~fib(1000)
 ```</code></pre>
 
@@ -62,8 +62,8 @@ will render as
         print(a, end=' ')
         a, b = b, a+b
     print()
-    ~ # hide me!
-    \~ # leave me be!
+    ~# hide me!
+    \~# leave me be!
 ~fib(1000)
 ```
 

src/renderer/html_handlebars/hbs_renderer.rs

@@ -897,7 +897,7 @@ impl BoringPattern {
     fn new_simple(prefix: &str) -> BoringPattern {
         BoringPattern {
             regex: Regex::new(&format!(
-                r"^(\s*)(?P<escape>\\)?{} ?(.*)$",
+                r"^(\s*)(?P<escape>\\)?{}(.*)$",
                 regex::escape(prefix)
             ))
             .unwrap(),