update elements and fix some bugs

lib/src/prism/components/prism-bison.js

Index: lib/src/prism/components/prism-bison.js
diff --git a/lib/src/prism/components/prism-bison.js b/lib/src/prism/components/prism-bison.js
new file mode 100644
index 0000000000000000000000000000000000000000..9a65a537d191f8831b75e3828ece5180dcbd49d3
--- /dev/null
+++ b/lib/src/prism/components/prism-bison.js
@@ -0,0 +1,39 @@
+Prism.languages.bison = Prism.languages.extend('c', {});
+
+Prism.languages.insertBefore('bison', 'comment', {
+	'bison': {
+		// This should match all the beginning of the file
+		// including the prologue(s), the bison declarations and
+		// the grammar rules.
+		pattern: /^[\s\S]*?%%[\s\S]*?%%/,
+		inside: {
+			'c': {
+				// Allow for one level of nested braces
+				pattern: /%\{[\s\S]*?%\}|\{(?:\{[^}]*\}|[^{}])*\}/,
+				inside: {
+					'delimiter': {
+						pattern: /^%?\{|%?\}$/,
+						alias: 'punctuation'
+					},
+					'bison-variable': {
+						pattern: /[$@](?:<[^\s>]+>)?[\w$]+/,
+						alias: 'variable',
+						inside: {
+							'punctuation': /<|>/
+						}
+					},
+					rest: Prism.languages.c
+				}
+			},
+			'comment': Prism.languages.c.comment,
+			'string': Prism.languages.c.string,
+			'property': /\S+(?=:)/,
+			'keyword': /%\w+/,
+			'number': {
+				pattern: /(^|[^@])\b(?:0x[\da-f]+|\d+)/i,
+				lookbehind: true
+			},
+			'punctuation': /%[%?]|[|:;\[\]<>]/
+		}
+	}
+});