Improve README formatting with highlighted blocks (#1055)

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readme.md

@@ -1,12 +1,11 @@
-TinyXML-2
-=========
+# TinyXML-2
 
 [![Test](https://github.com/leethomason/tinyxml2/actions/workflows/test.yml/badge.svg)](https://github.com/leethomason/tinyxml2/actions/workflows/test.yml)
 
 TinyXML-2 is a simple, small, efficient, C++ XML parser that can be
 easily integrated into other programs.
 
-The master is hosted on github:
+The master is hosted on GitHub:
 https://github.com/leethomason/tinyxml2
 
 The online HTML version of these docs:
@@ -14,8 +13,7 @@ http://leethomason.github.io/tinyxml2/
 
 Examples are in the "related pages" tab of the HTML docs.
 
-What it does.
--------------
+## What it does.
 
 In brief, TinyXML-2 parses an XML document, and builds from that a
 Document Object Model (DOM) that can be read, modified, and saved.
@@ -37,7 +35,7 @@ code without creating a document first.
 
 TinyXML-2 is designed to be easy and fast to learn. It is one header and
 one cpp file. Simply add these to your project and off you go.
-There is an example file - xmltest.cpp - to get you started.
+There is an example file - `xmltest.cpp` - to get you started.
 
 TinyXML-2 is released under the ZLib license,
 so you can use it in open source or commercial code. The details
@@ -45,10 +43,10 @@ of the license are at the top of every source file.
 
 TinyXML-2 attempts to be a flexible parser, but with truly correct and
 compliant XML output. TinyXML-2 should compile on any reasonably C++
-compliant system. It does not rely on exceptions, RTTI, or the STL.
+compliant system. It does not rely on exceptions, run-time type information,
+or the C++ Standard Library.
 
-What it doesn't do.
--------------------
+## What it doesn't do.
 
 TinyXML-2 doesn't parse or use DTDs (Document Type Definitions) or XSLs
 (eXtensible Stylesheet Language.) There are other parsers out there
@@ -56,8 +54,7 @@ that are much more fully featured. But they are generally bigger and
 more difficult to use. If you are working with
 browsers or have more complete XML needs, TinyXML-2 is not the parser for you.
 
-TinyXML-1 vs. TinyXML-2
------------------------
+## TinyXML-1 vs. TinyXML-2
 
 TinyXML-2 has long been the focus of all development. It is well tested 
 and should be used instead of TinyXML-1.
@@ -67,10 +64,10 @@ rich test cases. But the implementation of the parser is completely re-written
 to make it more appropriate for use in a game. It uses less memory, is faster,
 and uses far fewer memory allocations.
 
-TinyXML-2 has no requirement or support for STL.
+TinyXML-2 has no dependency on the C++ Standard Library, and does not adapt or use any
+of its collection types either.
 
-Features
---------
+## Features
 
 ### Code Page
 
@@ -81,17 +78,17 @@ Filenames for loading / saving are passed unchanged to the underlying OS.
 
 ### Memory Model
 
-An XMLDocument is a C++ object like any other, that can be on the stack, or
-new'd and deleted on the heap.
+An `XMLDocument` is a C++ object like any other, that can be on the stack, or
+`new`'d and `delete`d on the heap.
 
-However, any sub-node of the Document, XMLElement, XMLText, etc, can only
-be created by calling the appropriate XMLDocument::NewElement, NewText, etc.
+However, any sub-node of the `XMLDocument`, `XMLElement`, `XMLText`, etc, can only
+be created by calling the appropriate `XMLDocument::NewElement`, `XMLDocument::NewText`, etc.
 method. Although you have pointers to these objects, they are still owned
-by the Document. When the Document is deleted, so are all the nodes it contains.
+by the `XMLDocument`. When the `XMLDocument` is `delete`d, so are all the nodes it contains.
 
 ### White Space
 
-#### Whitespace Preservation (default, PRESERVE_WHITESPACE)
+#### Whitespace Preservation (default, `PRESERVE_WHITESPACE`)
 
 Microsoft has an excellent article on white space: http://msdn.microsoft.com/en-us/library/ms256097.aspx
 
@@ -103,51 +100,57 @@ line-feed character, as required by the XML spec.
 
 White space in text is preserved. For example:
 
-	<element> Hello,  World</element>
+```xml
+<element> Hello,  World</element>
+```
 
-The leading space before the "Hello" and the double space after the comma are
+The leading space before the `"Hello"` and the double space after the comma are
 preserved. Line-feeds are preserved, as in this example:
 
-	<element> Hello again,
-	          World</element>
+```xml
+<element> Hello again,
+          World</element>
+```
 
 However, white space between elements is **not** preserved. Although not strictly
 compliant, tracking and reporting inter-element space is awkward, and not normally
 valuable. TinyXML-2 sees these as the same XML:
 
-	<document>
-		<data>1</data>
-		<data>2</data>
-		<data>3</data>
-	</document>
+```xml
+<document>
+	<data>1</data>
+	<data>2</data>
+	<data>3</data>
+</document>
 
-	<document><data>1</data><data>2</data><data>3</data></document>
+<document><data>1</data><data>2</data><data>3</data></document>
+```
 
-#### Whitespace Collapse (COLLAPSE_WHITESPACE)
+#### Whitespace Collapse (`COLLAPSE_WHITESPACE`)
 
 For some applications, it is preferable to collapse whitespace. Collapsing
 whitespace gives you "HTML-like" behavior, which is sometimes more suitable
 for hand typed documents.
 
-TinyXML-2 supports this with the 'whitespace' parameter to the XMLDocument constructor.
+TinyXML-2 supports this with the `whitespace` parameter to the `XMLDocument` constructor.
 (The default is to preserve whitespace, as described above.)
 
-However, you may also use COLLAPSE_WHITESPACE, which will:
+However, you may also use `COLLAPSE_WHITESPACE`, which will:
 
 * Remove leading and trailing whitespace
 * Convert newlines and line-feeds into a space character
 * Collapse a run of any number of space characters into a single space character
 
-Note that (currently) there is a performance impact for using COLLAPSE_WHITESPACE.
+Note that (currently) there is a performance impact for using `COLLAPSE_WHITESPACE`.
 It essentially causes the XML to be parsed twice.
 
-#### Pedantic Whitespace (PEDANTIC_WHITESPACE)
+#### Pedantic Whitespace (`PEDANTIC_WHITESPACE`)
 
 For applications that need to know about text nodes that are composed entirely of 
-whitespace, PEDANTIC_WHITESPACE is available. PEDANTIC_WHITESPACE maintains all the
+whitespace, `PEDANTIC_WHITESPACE` is available. `PEDANTIC_WHITESPACE` maintains all the
 whitespace between elements. 
 
-PEDANTIC_WHITESPACE is a new mode and not as tested as the other whitespace modes.
+`PEDANTIC_WHITESPACE` is a new mode and not as tested as the other whitespace modes.
 
 ### Error Reporting
 
@@ -163,18 +166,22 @@ line number information for error messages.
 TinyXML-2 recognizes the pre-defined "character entities", meaning special
 characters. Namely:
 
-	&amp;	&
-	&lt;	<
-	&gt;	>
-	&quot;	"
-	&apos;	'
+```html
+&amp;	&
+&lt;	<
+&gt;	>
+&quot;	"
+&apos;	'
+```
 
 These are recognized when the XML document is read, and translated to their
 UTF-8 equivalents. For instance, text with the XML of:
 
-	Far &amp; Away
+```xml
+Far &amp; Away
+```
 
-will have the Value() of "Far & Away" when queried from the XMLText object,
+will have the `Value()` of `"Far & Away"` when queried from the `XMLText` object,
 and will be written back to the XML stream/file as an ampersand.
 
 Additionally, any character can be specified by its Unicode code point:
@@ -188,21 +195,27 @@ regular code point. The output is correct, but the entity syntax isn't preserved
 #### Print to file
 You can directly use the convenience function:
 
-	XMLDocument doc;
-	...
-	doc.SaveFile( "foo.xml" );
+```cpp
+XMLDocument doc;
+// ...
+doc.SaveFile("foo.xml");
+```
 
-Or the XMLPrinter class:
+Or the `XMLPrinter` class:
 
-	XMLPrinter printer( fp );
-	doc.Print( &printer );
+```cpp
+XMLPrinter printer(fp);
+doc.Print(&printer);
+```
 
 #### Print to memory
-Printing to memory is supported by the XMLPrinter.
+Printing to memory is supported by the `XMLPrinter`.
 
-	XMLPrinter printer;
-	doc.Print( &printer );
-	// printer.CStr() has a const char* to the XML
+```cpp
+XMLPrinter printer;
+doc.Print(&printer);
+// printer.CStr() has a const char* to the XML
+```
 
 #### Print without an XMLDocument
 
@@ -210,92 +223,95 @@ When loading, an XML parser is very useful. However, sometimes
 when saving, it just gets in the way. The code is often set up
 for streaming, and constructing the DOM is just overhead.
 
-The Printer supports the streaming case. The following code
+The `XMLPrinter` supports the streaming case. The following code
 prints out a trivially simple XML file without ever creating
 an XML document.
 
-	XMLPrinter printer( fp );
-	printer.OpenElement( "foo" );
-	printer.PushAttribute( "foo", "bar" );
-	printer.CloseElement();
+```cpp
+XMLPrinter printer(fp);
+printer.OpenElement("foo");
+printer.PushAttribute("foo", "bar");
+printer.CloseElement();
+```
 
-Examples
---------
+### Examples
 
 #### Load and parse an XML file.
 
-	/* ------ Example 1: Load and parse an XML file. ---- */
-	{
-		XMLDocument doc;
-		doc.LoadFile( "dream.xml" );
-	}
+```cpp
+/* ------ Example 1: Load and parse an XML file. ---- */
+{
+	XMLDocument doc;
+	doc.LoadFile("dream.xml");
+}
+```
 
 #### Lookup information.
 
-	/* ------ Example 2: Lookup information. ---- */
-	{
-		XMLDocument doc;
-		doc.LoadFile( "dream.xml" );
+```cpp
+/* ------ Example 2: Lookup information. ---- */
+{
+	XMLDocument doc;
+	doc.LoadFile("dream.xml");
 
-		// Structure of the XML file:
-		// - Element "PLAY"      the root Element, which is the
-		//                       FirstChildElement of the Document
-		// - - Element "TITLE"   child of the root PLAY Element
-		// - - - Text            child of the TITLE Element
+	// Structure of the XML file:
+	// - Element "PLAY"      the root Element, which is the
+	//                       FirstChildElement of the Document
+	// - - Element "TITLE"   child of the root PLAY Element
+	// - - - Text            child of the TITLE Element
 
-		// Navigate to the title, using the convenience function,
-		// with a dangerous lack of error checking.
-		const char* title = doc.FirstChildElement( "PLAY" )->FirstChildElement( "TITLE" )->GetText();
-		printf( "Name of play (1): %s\n", title );
+	// Navigate to the title, using the convenience function,
+	// with a dangerous lack of error checking.
+	const char* title = doc.FirstChildElement("PLAY")->FirstChildElement("TITLE")->GetText();
+	printf("Name of play (1): %s\n", title);
 
-		// Text is just another Node to TinyXML-2. The more
-		// general way to get to the XMLText:
-		XMLText* textNode = doc.FirstChildElement( "PLAY" )->FirstChildElement( "TITLE" )->FirstChild()->ToText();
-		title = textNode->Value();
-		printf( "Name of play (2): %s\n", title );
-	}
+	// Text is just another Node to TinyXML-2. The more
+	// general way to get to the XMLText:
+	XMLText* textNode = doc.FirstChildElement("PLAY")->FirstChildElement("TITLE")->FirstChild()->ToText();
+	title = textNode->Value();
+	printf("Name of play (2): %s\n", title);
+}
+```
 
-Using and Installing
---------------------
+## Using and Installing
 
 There are 2 files in TinyXML-2:
-* tinyxml2.cpp
-* tinyxml2.h
+* `tinyxml2.cpp`
+* `tinyxml2.h`
 
 And additionally a test file:
-* xmltest.cpp
+* `xmltest.cpp`
 
-Generally speaking, the intent is that you simply include the tinyxml2.cpp and 
-tinyxml2.h files in your project and build with your other source code.
+Generally speaking, the intent is that you simply include the `tinyxml2.cpp` and 
+`tinyxml2.h` files in your project and build with your other source code.
 
 There is also a CMake build included. CMake is the general build for TinyXML-2.
 
 (Additional build systems are costly to maintain, and tend to become outdated. They are
 being removed over time.)
 
-Building TinyXML-2 - Using vcpkg
---------------------------------
+### Building TinyXML-2 - Using vcpkg
 
 You can download and install TinyXML-2 using the [vcpkg](https://github.com/Microsoft/vcpkg) dependency manager:
 
-    git clone https://github.com/Microsoft/vcpkg.git
-    cd vcpkg
-    ./bootstrap-vcpkg.sh
-    ./vcpkg integrate install
-    ./vcpkg install tinyxml2
+```sh
+git clone https://github.com/Microsoft/vcpkg.git
+cd vcpkg
+./bootstrap-vcpkg.sh
+./vcpkg integrate install
+./vcpkg install tinyxml2
+```
 
 The TinyXML-2 port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please [create an issue or pull request](https://github.com/Microsoft/vcpkg) on the vcpkg repository.
 
-Versioning
-----------
+## Versioning
 
-TinyXML-2 uses semantic versioning. http://semver.org/ Releases are now tagged in github.
+TinyXML-2 uses semantic versioning. http://semver.org/ Releases are now tagged in GitHub.
 
 Note that the major version will (probably) change fairly rapidly. API changes are fairly
 common.
 
-License
--------
+## License
 
 TinyXML-2 is released under the zlib license:
 
@@ -316,8 +332,7 @@ must not be misrepresented as being the original software.
 3. This notice may not be removed or altered from any source
 distribution.
 
-Contributors
-------------
+## Contributors
 
 Thanks very much to everyone who sends suggestions, bugs, ideas, and
 encouragement. It all helps, and makes this project fun.