making progress on UDL docs

Author: pryrt

content/docs/user-defined-language-system.md

@@ -15,18 +15,36 @@ Using **Languages > Define Your Language...** will bring up a dialog box (which
 
 The main pulldowns and buttons are available, whichever configuration tab is active:
 * **User Language** pulldown lists all the existing UDL will allow you to select the UDL you would like to edit or examine.  There is a special entry for the default UDL, called **User Defined Language** here (though it shows up in the Notepad++ **Languages** menu as **User-Defined**), which can be used as a template for other UDL.
-* **Create New** will copy the default **User Defined Language** stylings and rules to a new name
-* **Save As** will copy the currently-selected UDL, with all its stylings and rules, to a new name
-* **Import...** will [import](#import-a-udl) a UDL XML file into your current instance ([see below](#import-a-udl))
-* **Export...** will save the UDL XML file to a location of your choosing; you can then share this with others, so that they can [import](#import-a-udl) your UDL for their own use
+* **Create New** will copy the default **User Defined Language** stylings and rules to a new name.
+* **Save As** will copy the currently-selected UDL, with all its stylings and rules, to a new name.
+* **Import...** will [import](#import-a-udl) a UDL XML file into your current instance ([see below](#import-a-udl)).
+* **Export...** will save the UDL XML file to a location of your choosing; you can then share this with others, so that they can [import](#import-a-udl) your UDL for their own use.
 * **Dock** or **Undock** will toggle whether the UDL dialog is a standalone dialog, or docked in the Notepad++ window.
-* ...
+* **☐ Ignore Case** will make the various keywords ignore case while matching.
+* **☐ Transparency** (when not docked) will make the dialog box semi-transparent; the slider bar changes from virtually invisible (all the way to the left) to mostly opaque (all the way to the right); if you want it completely opaque (no transparency), uncheck the box.
 
 When a UDL other than the default **User Defined Language** is seelcted in the pulldown, the following will also be available:
-* **Rename** will rename the existing UDL (only visible when a UDL other than the default **User Defined Language** is selected)
-*  ...
+* **Rename** will rename the currently-selected UDL.
+* **Remove** will delete the currently-selected UDL.
+* **Ext.: ____** will accept a list of zero or more extensions (without the period).  Files that match these extensions will be interpreted as belonging to the currently-selected UDL, and will be styled appropriately.  These extensions override the default extensions for pre-defined **Languages**, so if your UDL's extension conflicts with another language's extension, the UDL will take priority.
 
-Ivan Radić has created the definitive guide to the nuts and bolts of UDL version 2.1, which is available at [https://ivan-radic.github.io/udl-documentation/](https://ivan-radic.github.io/udl-documentation/).  He explains the details of what each of the tabs in the **User Defined Language** dialog box will do, and how to use them to style your various keywords.
+### UDL Configuration Tabs
+
+Ivan Radić has created the definitive guide to the nuts and bolts of UDL version 2.1, which is available at [https://ivan-radic.github.io/udl-documentation/]().  He explains the details of what each of the tabs in the **User Defined Language** dialog box will do, and how to use them to style your various keywords.  However, these descriptions will give you an overview of what each tab is for.
+
+* The **Folder & Default** tab allows setting the default style, setting up keywords (or characters) that will allow code folding, and setting up styles for those keywords.  The **Open**, **Middle**, and **Close** boxes under each folding-type define the triggers for the start, middle, and end of folding.  For example, with `if`, `else`, and `endif`, it will define fold regions so that you can fold from `if` to `else`, from `else` to `endif`, and (assuming there is no `else` clause) from `if` to `endif`.  **Folding in comment** allows comments to include folding; **Folding in code 1 style** allows the triggers to be touching something else (so with a trigger of `{`, it will match `if{` or `if {`), whereas **Folding in code 2 style** requires there be whitespace around the trigger (so `if{` would _not_ match an **Open**-trigger of `{`).
+
+* The **Keywords List** tab allows defining eight (8) different groups of keywords, so you can style different groups of words differently (like builtin functions vs. flow control keywords).  Separate each keyword by a space (and that means that spaces are not allowed in keywords unless you put quotes around the phrase).  If **☐ Prefix Mode** is enabled for a given group, that means that it will match anything that _starts_ with your string (so a keyword of `for` would match `for`, `forth`, and `format` if that option is enabled).
+
+    As a point of interest, you shouldn't have a given keyword in more than one keyword-group _or_ folder-group.  If you want `if`/`else`/`endif` to cause block-folding, do not also put them in one of your keyword-groups.
+
+* The **Comment & Number** tab allows setting styles for comments and for numbers.  
+    * **Line Comment Position** allows you to decide whether "line comments" can start anywhere on the line, must start at the beginning, or can only start after whitespace.
+    * **☐ Allow folding of comments** will enable comments to be foldable.
+    * **Comment line style** defines the style  for "line comments" -- comments that proceed from the opening-trigger to the end of the line.
+    * **Comment style** defines the style for multiline-comments.
+    * **Number style** defines the style for numbers
+        ... TODO ... how much detail to I want to replicate from Ivan here?
 
 ### Import a UDL
 
@@ -50,7 +68,8 @@ If you created or imported a UDL using the **User Defined Languages** dialog ins
 
 ## UDL and Themes
 
-... 
+... TODO ...
+
 <!--
 ## shared UDL files