Add support for automatic line numbers, and the \label and \ref macros (resolves issue #71)

config/default.js

@@ -262,6 +262,13 @@ MathJax.Hub.Config({
     //
     processEnvironments: true,
 
+    //
+    //  Conteols whether tex2jax processes \ref{...} commands outside
+    //  of math mode.  Set to "false" to prevent processing of \ref
+    //  except within math mode.
+    //  
+    processRefs: true,
+
     //
     //  Controls whether tex2jax inserts MathJax_Preview spans to make a
     //  preview available, and what preview to use, when it locates in-line
@@ -368,7 +375,19 @@ MathJax.Hub.Config({
     //        bold: ['{\\bf #1}', 1]
     //      }
     //
-    Macros: {}
+    Macros: {},
+    
+    //
+    //  Equation numbering parameters
+    //
+    equationNumbers: {
+      autoNumber: "none",   // "AMS" for standard AMS environment numbering,
+                            //  or "all" to number all displayed equations
+//    formatNumber: function (n) {return n},            // format for equation number n
+//    formatTag:    function (n) {return '('+n+')'},    // format for \tag and \eqref
+//    formatID:     function (n) {return 'mjx-eqn-'+n}, // element ID to use for reference
+//    formatURL:    function (n) {return '#mjx-eqn-'+escape(n)},  // URL to use for references
+    }
     
   },
 

jax/input/TeX/config.js

@@ -12,5 +12,5 @@
  *      http://www.apache.org/licenses/LICENSE-2.0
  */
 
-MathJax.InputJax.TeX=MathJax.InputJax({id:"TeX",version:"1.1.2",directory:MathJax.InputJax.directory+"/TeX",extensionDir:MathJax.InputJax.extensionDir+"/TeX",config:{TagSide:"right",TagIndent:"0.8em",MultLineWidth:"85%"}});MathJax.InputJax.TeX.Register("math/tex");MathJax.InputJax.TeX.loadComplete("config.js");
+MathJax.InputJax.TeX=MathJax.InputJax({id:"TeX",version:"1.1.3",directory:MathJax.InputJax.directory+"/TeX",extensionDir:MathJax.InputJax.extensionDir+"/TeX",config:{TagSide:"right",TagIndent:"0.8em",MultLineWidth:"85%",equationNumbers:{autoNumber:"none",formatNumber:function(a){return a},formatTag:function(a){return"("+a+")"},formatID:function(a){return"mjx-eqn-"+a},formatURL:function(a){return"#mjx-eqn-"+escape(a)}}}});MathJax.InputJax.TeX.Register("math/tex");MathJax.InputJax.TeX.loadComplete("config.js");
 

unpacked/config/default.js

@@ -262,6 +262,13 @@ MathJax.Hub.Config({
     //
     processEnvironments: true,
 
+    //
+    //  Conteols whether tex2jax processes \ref{...} commands outside
+    //  of math mode.  Set to "false" to prevent processing of \ref
+    //  except within math mode.
+    //  
+    processRefs: true,
+
     //
     //  Controls whether tex2jax inserts MathJax_Preview spans to make a
     //  preview available, and what preview to use, when it locates in-line
@@ -368,7 +375,19 @@ MathJax.Hub.Config({
     //        bold: ['{\\bf #1}', 1]
     //      }
     //
-    Macros: {}
+    Macros: {},
+    
+    //
+    //  Equation numbering parameters
+    //
+    equationNumbers: {
+      autoNumber: "none",   // "AMS" for standard AMS environment numbering,
+                            //  or "all" to number all displayed equations
+//    formatNumber: function (n) {return n},            // format for equation number n
+//    formatTag:    function (n) {return '('+n+')'},    // format for \tag and \eqref
+//    formatID:     function (n) {return 'mjx-eqn-'+n}, // element ID to use for reference
+//    formatURL:    function (n) {return '#mjx-eqn-'+escape(n)},  // URL to use for references
+    }
     
   },
 

unpacked/extensions/TeX/AMSmath.js

@@ -6,7 +6,7 @@
  *  
  *  ---------------------------------------------------------------------
  *  
- *  Copyright (c) 2009 Design Science, Inc.
+ *  Copyright (c) 2009-2011 Design Science, Inc.
  * 
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -21,16 +21,30 @@
  *  limitations under the License.
  */
 
-MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
+MathJax.Extension["TeX/AMSmath"] = {
-  var VERSION = "1.1";
+  version: "1.1.1",
   
-  var MML = MathJax.ElementJax.mml;
+  number: 0,        // current equation number
-  var TEX = MathJax.InputJax.TeX;
+  startNumber: 0,   // current starting equation number (for when equation is restarted)
-  var TEXDEF = TEX.Definitions;
+  labels: {},       // the set of labels
-  var STACKITEM = TEX.Stack.Item;
+  eqlabels: {},     // labels in the current equation
+  refs: []          // array of jax with unresolved references
+};
+
+MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
+  
+  var MML = MathJax.ElementJax.mml,
+      TEX = MathJax.InputJax.TeX,
+      AMS = MathJax.Extension["TeX/AMSmath"];
+
+  var TEXDEF = TEX.Definitions,
+      STACKITEM = TEX.Stack.Item,
+      CONFIG = TEX.config.equationNumbers;
       
   var COLS = function (W) {return W.join("em ") + "em"};
   
+  /******************************************************************************/
+  
   MathJax.Hub.Insert(TEXDEF,{
     macros: {
       mathring:   ['Accent','2DA'],  // or 0x30A
@@ -54,6 +68,9 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       
       tag:         'HandleTag',
       notag:       'HandleNoTag',
+      label:       'HandleLabel',
+      ref:         'HandleRef',
+      eqref:       ['HandleRef',true],
       
       substack:   ['Macro','\\begin{subarray}{c}#1\\end{subarray}',1],
       
@@ -101,7 +118,10 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       gathered:      ['Array',null,null,null,'c',null,".5em",'D'],
 
       subarray:      ['Array',null,null,null,null,COLS([0,0,0,0]),"0.1em",'S',1],
-      smallmatrix:   ['Array',null,null,null,'c',COLS([1/3]),".2em",'S',1]
+      smallmatrix:   ['Array',null,null,null,'c',COLS([1/3]),".2em",'S',1],
+      
+      'equation':    ['EquationBegin','Equation',true],
+      'equation*':   ['EquationBegin','EquationStar',false]
     },
     
     delimiter: {
@@ -113,21 +133,50 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
   });
     
 
+  /******************************************************************************/
+  
   TEX.Parse.Augment({
 
     /*
-     *  Add the tag to the environment to be added to the table row later
+     *  Add the tag to the environment (to be added to the table row later)
      */
     HandleTag: function (name) {
-      var arg = this.trimSpaces(this.GetArgument(name));
+      var arg = this.trimSpaces(this.GetArgument(name)), tag = arg;
-      if (arg === "*") {arg = this.GetArgument(name)} else {arg = "("+arg+")"}
+      if (arg === "*") {tag = arg = this.GetArgument(name)} else {arg = CONFIG.formatTag(arg)}
-      if (this.stack.global.notag)
+      var global = this.stack.global; global.tagID = tag;
-        {TEX.Error(name+" not allowed in "+this.stack.global.notag+" environment")}
+      if (global.notags) {TEX.Error(name+" not allowed in "+global.notags+" environment")}
-      if (this.stack.global.tag) {TEX.Error("Multiple "+name)}
+      if (global.tag) {TEX.Error("Multiple "+name)}
-      this.stack.global.tag = MML.mtd.apply(MML,this.InternalMath(arg));
+      global.tag = MML.mtd.apply(MML,this.InternalMath(arg)).With({id:CONFIG.formatID(tag)});
     },
     HandleNoTag: function (name) {
       if (this.stack.global.tag) {delete this.stack.global.tag}
+      this.stack.global.notag = true;  // prevent auto-tagging
+    },
+    
+    /*
+     *  Record a label name for a tag
+     */
+    HandleLabel: function (name) {
+      var global = this.stack.global, label = this.GetArgument(name);
+      if (!AMS.refUpdate) {
+        if (global.label) {TEX.Error("Multiple "+name+"'s")}
+        global.label = label;
+        if (AMS.labels[label] || AMS.eqlabels[label]) {TEX.Error("Label '"+label+"' mutiply defined")}
+        AMS.eqlabels[label] = "???"; // will be replaced by tag value later
+      }
+    },
+    
+    /*
+     *  Handle a label reference
+     */
+    HandleRef: function (name,eqref) {
+      var label = this.GetArgument(name);
+      var ref = AMS.labels[label] || AMS.eqlabels[label];
+      if (!ref) {ref = "??"; AMS.badref = !AMS.refUpdate}
+      var tag = ref; if (eqref) {tag = CONFIG.formatTag(tag)}
+      this.Push(MML.mrow.apply(MML,this.InternalMath(tag)).With({
+        href:CONFIG.formatURL(ref), "class":"MathJax_ref"
+      }));
     },
     
     /*
@@ -202,7 +251,6 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
         if (STYLE === "D") {frac.displaystyle = true; frac.scriptlevel = 0}
           else {frac.displaystyle = false; frac.scriptlevel = style - 1}
       }
-
       this.Push(frac);
     },
 
@@ -210,8 +258,8 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
      *  Implements multline environment (mostly handled through STACKITEM below)
      */
     Multline: function (begin,numbered) {
-      this.Push(begin);
+      this.Push(begin); this.checkEqnEnv();
-      return STACKITEM.multline().With({
+      return STACKITEM.multline(numbered,this.stack).With({
         arraydef: {
           displaystyle: true,
           rowspacing: ".5em",
@@ -226,7 +274,7 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
      *  Handle AMS aligned environments
      */
     AMSarray: function (begin,numbered,taggable,align,spacing) {
-      this.Push(begin);
+      this.Push(begin); if (taggable) {this.checkEqnEnv()}
       align = align.replace(/[^clr]/g,'').split('').join(' ');
       align = align.replace(/l/g,'left').replace(/r/g,'right').replace(/c/g,'center');
       return STACKITEM.AMSarray(begin.name,numbered,taggable,this.stack).With({
@@ -242,6 +290,9 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       });
     },
     
+    /*
+     *  Handle alignat environments
+     */
     AlignAt: function (begin,numbered,taggable) {
       var n = this.GetArgument("\\begin{"+begin.name+"}");
       if (n.match(/[^0-9]/)) {TEX.Error("Argument to \\begin{"+begin.name+"} must me a positive integer")}
@@ -252,6 +303,27 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       return this.Array(begin,null,null,align,spacing,".5em",'D');
     },
     
+    /*
+     *  Handle equation environment
+     */
+    EquationBegin: function (begin,force) {
+      this.checkEqnEnv();
+      this.stack.global.forcetag = (force && CONFIG.autoNumber !== "none");
+      return begin;
+    },
+    EquationStar: function (begin,row) {
+      this.stack.global.tagged = true; // prevent automatic tagging
+      return row;
+    },
+    
+    /*
+     *  Check for bad nesting of equation environments
+     */
+    checkEqnEnv: function () {
+      if (this.stack.global.eqnenv) {TEX.Error("Erroneous nesting of equation structures")}
+      this.stack.global.eqnenv = true;
+    },
+    
     /*
      *  Handle multiple integrals (make a mathop if followed by limits)
      */
@@ -268,6 +340,9 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       this.i = 0;
     },
     
+    /*
+     *  Handle stretchable arrows
+     */
     xArrow: function (name,chr,l,r) {
       var def = {width: "+"+(l+r)+"mu", lspace: l+"mu"};
       var bot = this.GetBrackets(name),
@@ -295,11 +370,43 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
     }
   });
   
+  /******************************************************************************/
+  
+  STACKITEM.Augment({
+    /*
+     *  Increment equation number and form tag mtd element
+     */
+    autoTag: function () {
+      var global = this.global;
+      if (!global.notag) {
+        AMS.number++; global.tagID = CONFIG.formatNumber(AMS.number.toString());
+        var mml = TEX.Parse("\\text{"+CONFIG.formatTag(global.tagID)+"}",{}).mml();
+        global.tag = MML.mtd(mml.With({id:CONFIG.formatID(global.tagID)}));
+      }
+    },
+  
+    /*
+     *  Get the tag and record the label, if any
+     */
+    getTag: function () {
+      var global = this.global, tag = global.tag; global.tagged = true;
+      if (global.label) {AMS.eqlabels[global.label] = global.tagID}
+      delete global.tag; delete global.tagID; delete global.label;
+      return tag;
+    }
+  });
+  
   /*
    *  Implement multline environment via a STACKITEM
    */
   STACKITEM.multline = STACKITEM.array.Subclass({
     type: "multline",
+    Init: function (numbered,stack) {
+      this.SUPER(arguments).Init.apply(this);
+      this.numbered = (numbered && CONFIG.autoNumber !== "none");
+      this.save = {notag: stack.global.notag};
+      stack.global.tagged = !numbered && !stack.global.forcetag; // prevent automatic tagging in starred environments
+    },
     EndEntry: function () {
       var mtd = MML.mtd.apply(MML,this.data);
       if (this.data.shove) {mtd.columnalign = this.data.shove}
@@ -317,37 +424,46 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
         if (!this.table[0][0].columnalign) {this.table[0][0].columnalign = MML.ALIGN.LEFT}
         if (!this.table[m][0].columnalign) {this.table[m][0].columnalign = MML.ALIGN.RIGHT}
         var mtr = MML.mtr;
-        if (this.global.tag) {
+        if (!this.global.tag && this.numbered) {this.autoTag()}
-          this.table[0] = [this.global.tag].concat(this.table[0]);
+        if (this.global.tag && !this.global.notags) {
-          delete this.global.tag; mtr = MML.mlabeledtr;
+          this.table[0] = [this.getTag()].concat(this.table[0]);
+          mtr = MML.mlabeledtr;
         }
         this.table[0] = mtr.apply(MML,this.table[0]);
         for (i = 1, m = this.table.length; i < m; i++)
           {this.table[i] = MML.mtr.apply(MML,this.table[i])}
       }
+      this.global.notag  = this.save.notag;
     }
   });
   
+  /*
+   *  Save data about numbering and taging equations, and add
+   *  tags at the ends of rows.
+   */
   STACKITEM.AMSarray = STACKITEM.array.Subclass({
     type: "AMSarray",
     Init: function (name,numbered,taggable,stack) {
       this.SUPER(arguments).Init.apply(this);
-      this.numbered = numbered;
+      this.numbered = (numbered && CONFIG.autoNumber !== "none");
-      this.save_notag = stack.global.notag;
+      this.save = {notags: stack.global.notags, notag: stack.global.notag};
-      stack.global.notag = (taggable ? null : name);
+      stack.global.notags = (taggable ? null : name);
+      stack.global.tagged = !numbered && !stack.global.forcetag; // prevent automatic tagging in starred environments
     },
     EndRow: function () {
       var mtr = MML.mtr;
-      if (this.global.tag) {
+      if (!this.global.tag && this.numbered) {this.autoTag()}
-        this.row = [this.global.tag].concat(this.row);
+      if (this.global.tag &&! this.global.notags) {
+        this.row = [this.getTag()].concat(this.row);
         mtr = MML.mlabeledtr;
-        delete this.global.tag;
       }
+      if (this.numbered) {delete this.global.notag}
       this.table.push(mtr.apply(MML,this.row)); this.row = [];
     },
     EndTable: function () {
       this.SUPER(arguments).EndTable.call(this);
-      this.global.notag = this.save_notag;
+      this.global.notags = this.save.notags;
+      this.global.notag  = this.save.notag;
     }
   });
   
@@ -358,9 +474,11 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
     oldCheckItem: STACKITEM.start.prototype.checkItem,
     checkItem: function (item) {
       if (item.type === "stop") {
-        var mml = this.mmlData();
+        var mml = this.mmlData(), global = this.global;
-        if (this.global.tag) {
+        if (AMS.display && !global.tag && !global.tagged && !global.isInner &&
-          var row = [this.global.tag,MML.mtd(mml)]; delete this.global.tag;
+            (CONFIG.autoNumber === "all" || global.forcetag)) {this.autoTag()}
+        if (global.tag) {
+          var row = [this.getTag(),MML.mtd(mml)];
           var def = {
             side: TEX.config.TagSide,
             minlabelspacing: TEX.config.TagIndent,
@@ -383,10 +501,44 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
         }
         return STACKITEM.mml(mml);
       }
-      return this.SUPER(arguments).checkItem.call(this,item);
+      return this.oldCheckItem.call(this,item);
     }
   });
   
+  /******************************************************************************/
+
+  /*
+   *  Add pre- and post-filters to handle the equation number maintainance.
+   */
+  TEX.prefilterHooks.Add(function (data) {
+    AMS.display = data.display;
+    AMS.number = AMS.startNumber;  // reset equation numbers (in case the equation restarted)
+    AMS.eqlabels = {}; AMS.badref = false;
+    if (AMS.refUpdate) {AMS.number = data.script.MathJax.startNumber}
+  });
+  TEX.postfilterHooks.Add(function (data) {
+    data.script.MathJax.startNumber = AMS.startNumber;
+    AMS.startNumber = AMS.number;                // equation numbers for next equation
+    MathJax.Hub.Insert(AMS.labels,AMS.eqlabels); // save labels from this equation
+    if (AMS.badref && !data.math.isError) {AMS.refs.push(data.script)}  // reprocess later
+  });
+  
+  MathJax.Hub.Register.MessageHook("Begin Math Input",function () {
+    AMS.refs = [];                 // array of jax with bad references
+    AMS.refUpdate = false;
+  });
+  MathJax.Hub.Register.MessageHook("End Math Input",function (message) {
+    if (AMS.refs.length) {
+      AMS.refUpdate = true;
+      for (var i = 0, m = AMS.refs.length; i < m; i++)
+        {AMS.refs[i].MathJax.state = MathJax.ElementJax.STATE.UPDATE}
+      return MathJax.Hub.processInput(AMS.refs);
+    }
+    return null;
+  });
+
+  /******************************************************************************/
+
   MathJax.Hub.Startup.signal.Post("TeX AMSmath Ready");
   
 });

unpacked/extensions/tex2jax.js

@@ -24,7 +24,7 @@
  */
 
 MathJax.Extension.tex2jax = {
-  version: "1.1.2",
+  version: "1.1.3",
   config: {
     inlineMath: [              // The start/stop pairs for in-line math
 //    ['$','$'],               //  (comment out any you don't want, or add your own, but
@@ -56,6 +56,8 @@ MathJax.Extension.tex2jax = {
     processEnvironments: true, // set to true to process \begin{xxx}...\end{xxx} outside
                                //   of math mode, false to prevent that
 
+    processRefs: true,         // set to true to process \ref{...} outside of math mode
+
     preview: "TeX"             // set to "none" to not insert MathJax_Preview spans
                                //   or set to an array specifying an HTML snippet
                                //   to use the same preview for every equation.
@@ -98,7 +100,8 @@ MathJax.Extension.tex2jax = {
     this.start = new RegExp(
       starts.sort(this.sortLength).join("|") + 
       (config.processEnvironments ? "|\\\\begin\\{([^}]*)\\}" : "") + 
-        (config.processEscapes ? "|\\\\*\\\\\\\$" : ""), "g"
+      (config.processEscapes ? "|\\\\*\\\\\\\$" : "") +
+      (config.processRefs ? "|\\\\(eq)?ref\\{[^}]*\\}" : ""), "g"
     );
     this.skipTags = new RegExp("^("+config.skipTags.join("|")+")$","i");
     this.ignoreClass = new RegExp("(^| )("+config.ignoreClass+")( |$)");
@@ -172,6 +175,12 @@ MathJax.Extension.tex2jax = {
         isBeginEnd: true
       };
       this.switchPattern(this.endPattern(this.search.end));
+    } else if (match[0].substr(0,4) === "\\ref" || match[0].substr(0,6) === "\\eqref") {
+      this.search = {
+        mode: "", end: "", open: element,
+        olen: 0, opos: this.pattern.lastIndex - match[0].length,
+      }
+      return this.endMatch([""],element);
     } else {                                         // escaped dollar signs
       var dollar = match[0].replace(/\\(.)/g,'$1');
       element.nodeValue = element.nodeValue.substr(0,match.index) + dollar +

unpacked/jax/input/TeX/config.js

@@ -24,14 +24,23 @@
 
 MathJax.InputJax.TeX = MathJax.InputJax({
   id: "TeX",
-  version: "1.1.2",
+  version: "1.1.3",
   directory: MathJax.InputJax.directory + "/TeX",
   extensionDir: MathJax.InputJax.extensionDir + "/TeX",
   
   config: {
     TagSide:       "right",
     TagIndent:     "0.8em",
-    MultLineWidth: "85%"
+    MultLineWidth: "85%",
+    
+    equationNumbers: {
+      autoNumber: "none",  // "AMS" for standard AMS numbering,
+                           //  or "all" for all displayed equations
+      formatNumber: function (n) {return n},
+      formatTag:    function (n) {return '('+n+')'},
+      formatID:     function (n) {return 'mjx-eqn-'+n},
+      formatURL:    function (n) {return '#mjx-eqn-'+escape(n)}
+    }
   }
 });
 MathJax.InputJax.TeX.Register("math/tex");

unpacked/jax/input/TeX/jax.js

@@ -850,8 +850,10 @@
         
         tag:               ['Extension','AMSmath'],
         notag:             ['Extension','AMSmath'],
-        label:             ['Macro','',1],           // not implemented yet
+        label:             ['Extension','AMSmath'],
-        nonumber:          ['Macro',''],             // not implemented yet
+        ref:               ['Extension','AMSmath'],
+        eqref:             ['Extension','AMSmath'],
+        nonumber:          ['Macro','\\notag'],
 
         //  Extensions to TeX
         unicode:           ['Extension','unicode'],
@@ -1627,7 +1629,7 @@
     InternalMath: function (text,level) {
       var def = {displaystyle: FALSE}; if (level != null) {def.scriptlevel = level}
       if (this.stack.env.font) {def.mathvariant = this.stack.env.font}
-      if (!text.match(/\$|\\\(/)) {return [this.InternalText(text,def)]}
+      if (!text.match(/\$|\\\(|\\(eq)?ref\s*\{/)) {return [this.InternalText(text,def)]}
       var i = 0, k = 0, c, match = '';
       var mml = [];
       while (i < text.length) {
@@ -1640,7 +1642,14 @@
             if (k < i-1) {mml.push(this.InternalText(text.slice(k,i-1),def))}
             match = '$'; k = i;
           }
+        } else if (c === '}' && match === '}') {
+          mml.push(MML.TeXAtom(TEX.Parse(text.slice(k,i),{}).mml().With(def)));
+          match = ''; k = i+1;
         } else if (c === '\\') {
+          if (match === '' && text.substr(i).match(/^(eq)?ref\s*\{/)) {
+            if (k < i-1) {mml.push(this.InternalText(text.slice(k,i-1),def))}
+            match = '}'; k = i-1;
+          } else {
             c = text.charAt(i++);
             if (c === '(' && match === '') {
               if (k < i-2) {mml.push(this.InternalText(text.slice(k,i-2),def))}
@@ -1651,6 +1660,7 @@
             }
           }
         }
+      }
       if (match !== '') {TEX.Error("Math not terminated in text box")}
       if (k < text.length) {mml.push(this.InternalText(text.slice(k),def))}
       return mml;