Extract grammar

Grammar is now defined in <!-- GRAMMAR --> blocks. The actually
displayed grammar will be auto-generated.

Author: nikic

.gitignore

@@ -1 +1,2 @@
 /.commit-template
+*.swp

spec/04-basic-concepts.md

@@ -3,6 +3,25 @@
 A PHP *program* consists of one or more source files, known formally as
 *scripts*.
 
+<!-- GRAMMAR
+script:
+  script-section
+  script script-section
+
+script-section:
+  text? start-tag statement-list? end-tag? text?
+
+start-tag:
+  '<?php'
+  '<?='
+
+end-tag:
+  '?>'
+
+text:
+  "arbitrary text not containing any of" start-tag "sequences"
+-->
+
 <pre>
   <i>script:</i>
     <i>script-section</i>

spec/05-types.md

@@ -119,6 +119,25 @@ the requirements of a numeric string, and whose trailing characters are
 non-numeric. A *non-numeric string* is a string that is not a numeric
 string.
 
+<!-- GRAMMAR
+str-numeric::
+  str-whitespace? sign? str-number
+
+str-whitespace::
+  str-whitespace? str-whitespace-char
+
+str-whitespace-char::
+  new-line
+  "Space character (U+0020)"
+  "Horizontal-tab character (U+0009)"
+  "Vertical-tab character (U+000B)"
+  "Form-feed character (U+000C)"
+
+str-number::
+  digit-sequence
+  floating-literal
+-->
+
 <pre>
   <i>str-numeric::</i>
     <i>str-whitespace<sub>opt</sub>   sign<sub>opt</sub>   str-number</i>

spec/07-variables.md

@@ -266,6 +266,21 @@ $b = &colors[100];      // a VSlot for $b is created which points to the array
 
 **Syntax**
 
+<!-- GRAMMAR
+function-static-declaration:
+  'static' static-variable-name-list ';'
+
+static-variable-name-list:
+  static-variable-declaration
+  static-variable-name-list ',' static-variable-declaration
+
+static-variable-declaration:
+  variable-name function-static-initializer?
+
+function-static-initializer:
+  '=' constant-expression
+-->
+
 <pre>
   <i>function-static-declaration:</i>
     static <i>static-variable-name-list</i>  ;
@@ -350,6 +365,15 @@ echo "\$fs = $fs\n";    // $fs = 3
 
 **Syntax**
 
+<!-- GRAMMAR
+global-declaration:
+  'global' variable-name-list ';'
+
+variable-name-list:
+  simple-variable
+  variable-name-list ',' simple-variable
+-->
+
 <pre>
   <i>global-declaration:</i>
     global <i>variable-name-list</i> ;