rearrange block types to optimize performance

Parsedown.php

@@ -217,56 +217,14 @@ private function parse_block_elements(array $lines, $context = '')
 
 			# Quick Paragraph 
 
-			if ($line[0] >= 'A' and $line['0'] !== '_')
+			if ($line[0] >= 'A' and $line[0] !== '_')
 			{
 				goto paragraph; # trust me 
 			}
 
-			# Setext Header (---) 
-
-			if ($element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[-]+[ ]*$/', $line))
-			{
-				$element['type'] = 'h.';
-				$element['level'] = 2;
-
-				continue;
-			}
-
-			# Horizontal Rule  
-
-			if (preg_match('/^[ ]{0,3}([-*_])([ ]{0,2}\1){2,}[ ]*$/', $line))
-			{
-				$elements []= $element;
-
-				$element = array(
-					'type' => 'hr',
-				);
-
-				continue;
-			}
-
-			# List Item 
-
-			if (preg_match('/^([ ]{0,3})(\d+[.]|[*+-])[ ](.*)/', $line, $matches))
-			{
-				$elements []= $element;
-
-				$element = array(
-					'type' => 'li',
-					'ordered' => isset($matches[2][1]),
-					'indentation' => $matches[1],
-					'last' => true,
-					'lines' => array(
-						preg_replace('/^[ ]{0,4}/', '', $matches[3]),
-					),
-				);
-
-				continue;
-			}
-
 			# Code 
 
-			if (preg_match('/^[ ]{4}(.*)/', $line, $matches))
+			if ($line[0] === ' ' and preg_match('/^[ ]{4}(.*)/', $line, $matches))
 			{
 				if ($element['type'] === 'code')
 				{
@@ -279,10 +237,20 @@ private function parse_block_elements(array $lines, $context = '')
 					$elements []= $element;
 
 					$element = array(
-						'type' => 'code', 
+						'type' => 'code',
 						'text' => $matches[1],
 					);
 				}
+
+				continue;
+			}
+
+			# Setext Header (---)  
+
+			if ($line[0] === '-' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[-]+[ ]*$/', $line))
+			{
+				$element['type'] = 'h.';
+				$element['level'] = 2;
 
 				continue;
 			}
@@ -296,17 +264,31 @@ private function parse_block_elements(array $lines, $context = '')
 				$level = strlen($matches[1]);
 
 				$element = array(
-					'type' => 'h.', 
-					'text' => $matches[2], 
+					'type' => 'h.',
+					'text' => $matches[2],
 					'level' => $level,
 				);
 
 				continue;
 			}
 
+			# Setext Header (===) 
+
+			if ($line[0] === '=' and $element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[=]+[ ]*$/', $line))
+			{
+				$element['type'] = 'h.';
+				$element['level'] = 1;
+
+				continue;
+			}
+
+			# ~  
+
+			$pure_line = ltrim($line);
+
 			# Blockquote 
 
-			if (preg_match('/^[ ]*>[ ]?(.*)/', $line, $matches))
+			if ($pure_line[0] === '>' and preg_match('/^>[ ]?(.*)/', $pure_line, $matches))
 			{
 				if ($element['type'] === 'blockquote')
 				{
@@ -334,45 +316,72 @@ private function parse_block_elements(array $lines, $context = '')
 				continue;
 			}
 
-			# Setext Header (===) 
+			# HTML  
 
-			if ($element['type'] === 'p' and ! isset($element['interrupted']) and preg_match('/^[=]+[ ]*$/', $line))
+			if ($pure_line[0] === '<')
 			{
-				$element['type'] = 'h.';
-				$element['level'] = 1;
+				# Block-Level HTML <self-closing/>
+
+				if (preg_match('{^<.+?/>$}', $pure_line))
+				{
+					$elements []= $element;
+
+					$element = array(
+						'type' => '',
+						'text' => $pure_line,
+					);
+
+					continue;
+				}
 
-				continue;
-			}
+				# Block-Level HTML <open>
 
-			# Block-Level HTML <self-closing/> 
+				if (preg_match('{^<(\w+)(?:[ ].*?)?>}', $pure_line, $matches))
+				{
+					$elements []= $element;
+
+					$element = array(
+						'type' => 'block',
+						'subtype' => strtolower($matches[1]),
+						'text' => $pure_line,
+						'depth' => 0,
+					);
+
+					preg_match('{</'.$matches[1].'>\s*$}', $pure_line) and $element['closed'] = true;
+
+					continue;
+				}
+			}
+
+			# Horizontal Rule   
 
-			if (preg_match('{^<.+?/>$}', $line))
+			if (preg_match('/^([-*_])([ ]{0,2}\1){2,}[ ]*$/', $pure_line))
 			{
 				$elements []= $element;
 
 				$element = array(
-					'type' => '',
-					'text' => $line,
+					'type' => 'hr',
 				);
 
 				continue;
 			}
 
-			# Block-Level HTML <open>
+			# List Item 
 
-			if (preg_match('{^<(\w+)(?:[ ].*?)?>}', $line, $matches))
+			if (preg_match('/^([ ]*)(\d+[.]|[*+-])[ ](.*)/', $line, $matches))
 			{
 				$elements []= $element;
 
 				$element = array(
-					'type' => 'block',
-					'subtype' => strtolower($matches[1]),
-					'text' => $line,
-					'depth' => 0,
+					'type' => 'li',
+					'ordered' => isset($matches[2][1]),
+					'indentation' => $matches[1],
+					'last' => true,
+					'lines' => array(
+						preg_replace('/^[ ]{0,4}/', '', $matches[3]),
+					),
 				);
 
-				preg_match('{</'.$matches[1].'>\s*$}', $line) and $element['closed'] = true; 
-
 				continue;
 			}
 

tests/data/sparse_list.html

@@ -1,14 +1,16 @@
-<p>Here's a list where items are separated by empty lines:</p>
-<ul>
-<li>
-<p>list item</p>
-</li>
-<li>another list item</li>
-</ul>
-<p>Here's an ordered one:</p>
-<ol>
-<li>
-<p>item one</p>
-</li>
-<li>item two</li>
-</ol>
+<p>Here's a sparse list:</p>
+<ul>
+<li>
+<p>list item</p>
+</li>
+<li>another list item</li>
+</ul>
+<p>Here's one with an indented list item:</p>
+<ul>
+<li>
+<p>li</p>
+<ul>
+<li>li</li>
+</ul>
+</li>
+</ul>

tests/data/sparse_list.md

@@ -1,11 +1,11 @@
-Here's a list where items are separated by empty lines:
-
-- list item
-
-- another list item
-
-Here's an ordered one:
-
-1. item one
-
-2. item two
+Here's a sparse list:
+
+- list item
+
+- another list item
+
+Here's one with an indented list item:
+
+- li
+
+    - li