Refactored away from having the underscore string library added to the String prototype.

app/core/Router.coffee

@@ -107,7 +107,7 @@ module.exports = class CocoRouter extends Backbone.Router
     window.location.href = window.location.href
 
   routeDirectly: (path, args) ->
-    path = "views/#{path}" if not _.str.startsWith(path, 'views/')
+    path = "views/#{path}" if not _.string.startsWith(path, 'views/')
     ViewClass = @tryToLoadModule path
     if not ViewClass and application.moduleLoader.load(path)
       @listenToOnce application.moduleLoader, 'load-complete', ->

app/core/deltas.coffee

@@ -118,7 +118,7 @@ module.exports.getConflicts = (headDeltas, pendingDeltas) ->
       offset += 1
 
       # these stop being substrings of each other? Then conflict DNE
-      if not (nextPath.startsWith path) then break
+      if not (_.string.startsWith nextPath, path) then break
 
       # check if these two are from the same group, but we still need to check for more beyond
       unless headPathMap[path] or headPathMap[nextPath] then continue

app/core/initialize.coffee

@@ -25,8 +25,8 @@ init = ->
   watchForErrors()
   setUpIOSLogging()
   path = document.location.pathname
-  app.testing = path.startsWith '/test'
-  app.demoing = path.startsWith '/demo'
+  app.testing = _.string.startsWith path, '/test'
+  app.demoing = _.string.startsWith path, '/demo'
   initializeUtilityServices() unless app.testing or app.demoing
   setUpBackboneMediator()
   app.initialize()

app/lib/surface/Lank.coffee

@@ -197,7 +197,7 @@ module.exports = Lank = class Lank extends CocoClass
   showAreaOfEffects: ->
     return unless @thang?.currentEvents
     for event in @thang.currentEvents
-      continue unless event.startsWith 'aoe-'
+      continue unless _.string.startsWith event, 'aoe-'
       continue if @handledDisplayEvents[event]
       @handledDisplayEvents[event] = true
       args = JSON.parse(event[4...])
@@ -240,7 +240,7 @@ module.exports = Lank = class Lank extends CocoClass
   showTextEvents: ->
     return unless @thang?.currentEvents
     for event in @thang.currentEvents
-      continue unless event.startsWith 'text-'
+      continue unless _.string.startsWith event, 'text-'
       continue if @handledDisplayEvents[event]
       @handledDisplayEvents[event] = true
       options = JSON.parse(event[5...])

app/lib/surface/LayerAdapter.coffee

@@ -199,7 +199,7 @@ module.exports = LayerAdapter = class LayerAdapter extends CocoClass
       @upsertActionToRender(lank.thangType)
     else
       for action in _.values(lank.thangType.getActions())
-        continue unless _.any @defaultActions, (prefix) -> action.name.startsWith(prefix)
+        continue unless _.any @defaultActions, (prefix) -> _.string.startsWith(action.name, prefix)
         @upsertActionToRender(lank.thangType, action.name, lank.options.colorConfig)
 
   upsertActionToRender: (thangType, actionName, colorConfig) ->

app/lib/surface/SegmentedSprite.coffee

@@ -38,7 +38,7 @@ module.exports = class SegmentedSprite extends createjs.SpriteContainer
     @actionNotSupported = false
 
     action = @thangType.getActions()[actionName]
-    randomStart = actionName.startsWith('move')
+    randomStart = _.string.startsWith(actionName, 'move')
     
     # because the resulting segmented image is set to the size of the movie clip, you can use
     # the raw registration data without scaling it.

app/lib/surface/SingularSprite.coffee

@@ -20,7 +20,7 @@ module.exports = class SingularSprite extends createjs.Sprite
     @actionNotSupported = false
 
     action = @thangType.getActions()[actionName]
-    randomStart = actionName.startsWith('move')
+    randomStart = _.string.startsWith(actionName, 'move')
     reg = action.positions?.registration or @thangType.get('positions')?.registration or {x:0, y:0}
 
     if action.animation

app/models/ThangType.coffee

@@ -291,7 +291,7 @@ module.exports = class ThangType extends CocoModel
 
   uploadGenericPortrait: (callback, src) ->
     src ?= @getPortraitSource()
-    return callback?() unless src and src.startsWith 'data:'
+    return callback?() unless src and _.string.startsWith src, 'data:'
     src = src.replace('data:image/png;base64,', '').replace(/\ /g, '+')
     body =
       filename: 'portrait.png'

app/views/DemoView.coffee

@@ -68,7 +68,7 @@ module.exports = DemoView = class DemoView extends RootView
     @demoFiles = @getAllDemoFiles()
     if @subPath
       prefix = DEMO_REQUIRE_PREFIX + @subPath
-      @demoFiles = (f for f in @demoFiles when f.startsWith prefix)
+      @demoFiles = (f for f in @demoFiles when _.string.startsWith f, prefix)
 
   runDemo: ->
     # TODO: Maybe have an option to run all demos in this folder at the same time?

app/views/HomeView.coffee

@@ -27,7 +27,7 @@ module.exports = class HomeView extends RootView
       c.isOldBrowser = true if $.browser.safari && majorVersion < 6  # 6 might have problems with Aether, or maybe just old minors of 6: https://errorception.com/projects/51a79585ee207206390002a2/errors/547a202e1ead63ba4e4ac9fd
     else
       console.warn 'no more jquery browser version...'
-    c.isEnglish = (me.get('preferredLanguage') or 'en').startsWith 'en'
+    c.isEnglish = _.string.startsWith (me.get('preferredLanguage') or 'en'), 'en'
     c.languageName = me.get('preferredLanguage')
     c.explainsHourOfCode = @explainsHourOfCode
     c.isMobile = @isMobile()

app/views/TestView.coffee

@@ -42,7 +42,7 @@ module.exports = TestView = class TestView extends RootView
     @specFiles = TestView.getAllSpecFiles()
     if @subPath
       prefix = TEST_REQUIRE_PREFIX + @subPath
-      @specFiles = (f for f in @specFiles when f.startsWith prefix)
+      @specFiles = (f for f in @specFiles when _.string.startsWith f, prefix)
 
   @runTests: (specFiles) ->
     specFiles ?= @getAllSpecFiles()

app/views/editor/thang/ThangTypeEditView.coffee

@@ -544,7 +544,7 @@ module.exports = class ThangTypeEditView extends RootView
     return @stopShowingSelectedNode() if not selected
     path = selected.getPath()
     parts = path.split('/')
-    return @stopShowingSelectedNode() unless parts.length >= 4 and path.startsWith '/raw/'
+    return @stopShowingSelectedNode() unless parts.length >= 4 and _.string.startsWith path, '/raw/'
     key = parts[3]
     type = parts[2]
     vectorParser = new SpriteBuilder(@thangType)

app/views/i18n/I18NHomeView.coffee

@@ -72,10 +72,10 @@ module.exports = class I18NHomeView extends RootView
 
   updateCoverage: ->
     selectedBase = @selectedLanguage[..2]
-    relatedLanguages = (l for l in languages when l.startsWith(selectedBase) and l isnt @selectedLanguage)
+    relatedLanguages = (l for l in languages when _.string.startsWith(l, selectedBase) and l isnt @selectedLanguage)
     for model in @aggregateModels.models
       @updateCoverageForModel(model, relatedLanguages)
-      model.generallyCovered = true if @selectedLanguage.startsWith 'en'
+      model.generallyCovered = true if _.string.startsWith @selectedLanguage, 'en'
     @aggregateModels.sort()
       
   updateCoverageForModel: (model, relatedLanguages) ->

app/views/ladder/LadderView.coffee

@@ -98,7 +98,7 @@ module.exports = class LadderView extends RootView
 
   onClickedLink: (e) ->
     link = $(e.target).closest('a').attr('href')
-    if link?.startsWith('/play/level') and me.get('anonymous')
+    if link? and _.string.startsWith(link, '/play/level') and me.get('anonymous')
       e.stopPropagation()
       e.preventDefault()
       @showApologeticSignupModal()

vendor/scripts/jasmine-mock-ajax.js

@@ -529,7 +529,7 @@ getJasmineRequireObj().AjaxRequestTracker = function() {
         var requests = jasmine.Ajax.requests.all().slice();
         for(var j in requests) {
           var request = requests[j];
-          if(request.url.startsWith(url)) {
+          if(_.string.startsWith(request.url, url)) {
             request.respondWith({status: 200, responseText: JSON.stringify(responseBody)});
             responded = true;
             break;