override print() by default, to avoid errors when using the browser print() (print to printer) if it hasn't been overridden. Overriding is now possible through Module.print

3 files changed, 12 insertions, 19 deletions

diff --git a/src/compiler.js b/src/compiler.js
index 33f0e1fb..655fd9a6 100644
--- a/src/compiler.js
+++ b/src/compiler.js
@@ -52,11 +52,7 @@ if (ENVIRONMENT_IS_NODE) {
   }
 
 } else if (ENVIRONMENT_IS_WEB) {
-  // Warning: We do not override print here, so that you can define it before
-  //          this code runs. However, if you do not define it and it is actually
-  //          called, it will try to print to a printer, and/or give odd errors.
-
-  printErr = function(x) {
+  print = printErr = function(x) {
     console.log(x);
   };
 
diff --git a/src/shell.html b/src/shell.html
index 87c285ea..c096a314 100644
--- a/src/shell.html
+++ b/src/shell.html
@@ -9,23 +9,21 @@
     <div id='output'></div>
     <hr>
     <script type='text/javascript'>
-      // implement print
-      var print = (function() {
-        var element = document.getElementById('output');
-        return function(text) {
-          element.innerHTML += text.replace('\n', '<br>', 'g') + '<br>';
-        };
-      })();
-
       // connect to canvas
       var Module = {
+        print: (function() {
+          var element = document.getElementById('output');
+          return function(text) {
+            element.innerHTML += text.replace('\n', '<br>', 'g') + '<br>';
+          };
+        })(),
         canvas: document.getElementById('canvas')
       };
       try {
         Module.ctx2D = Module.canvas.getContext('2d');
         if (!Module.ctx2D) throw 'Could not create canvas :(';
       } catch (e) {
-        print('(canvas not available)');
+        Module.print('(canvas not available)');
       }
 
       // The compiled code
diff --git a/src/shell.js b/src/shell.js
index 850dfd81..d67cc45a 100644
--- a/src/shell.js
+++ b/src/shell.js
@@ -44,11 +44,7 @@ if (ENVIRONMENT_IS_NODE) {
   }
 
 } else if (ENVIRONMENT_IS_WEB) {
-  // Warning: We do not override print here, so that you can define it before
-  //          this code runs. However, if you do not define it and it is actually
-  //          called, it will try to print to a printer, and/or give odd errors.
-
-  printErr = function(x) {
+  print = printErr = function(x) {
     console.log(x);
   };
 
@@ -99,6 +95,9 @@ try {
 if (!Module.arguments) {
   Module.arguments = arguments_;
 }
+if (Module.print) {
+  print = Module.print;
+}
 
   {{BODY}}