140295 2015-01-09 10:03:37 -0800 (function(arg1) {}.bind(window)).length results in 0 2020-08-21 11:49:24 -0700 1 1 1 Unclassified WebKit JavaScriptCore 528+ (Nightly build) Unspecified Unspecified RESOLVED WORKSFORME InRadar P2 Normal --- 1 sarimarton webkit-unassigned ashvayka dbates ggaren mark.lam webkit-bug-importer oldest_to_newest 1060163 0 sarimarton 2015-01-09 10:03:37 -0800 Simple as that: (function(arg1) {}.bind(window)).length results in 0 instead of 1. 1060207 1 webkit-bug-importer 2015-01-09 11:47:05 -0800 <rdar://problem/19429047> 1060758 2 dbates 2015-01-12 20:40:47 -0800 What is the version of Safari/WebKit you are using? What is the platform/OS version? On Mac, you can find the Safari/WebKit and OS version information in Safari > About Safari and Apple (menu) > About this Mac, respectively. I'm neither able to reproduce this bug using shipping Safari Version 8.0.2 (10600.2.5) on 10.10.1 (14B25) nor with the latest WebKit nightly r178255 on the same OS. I also was unable to reproduce this bug using Mac nightly r178109 (2015-01-08 15:33:34 GMT). That is, the expression "(function(arg1) {}.bind(window)).length" evaluates to 1 in Web Inspector. 1060805 3 sarimarton 2015-01-13 05:11:03 -0800 I'm using PhantomJS 1.9.7 on Windows and Unix. 1682007 4 ashvayka 2020-08-21 11:49:24 -0700 (In reply to sarimarton from comment #0) > (function(arg1) {}.bind(window)).length results in 0 instead of 1. (In reply to sarimarton from comment #3) > I'm using PhantomJS 1.9.7 on Windows and Unix. At that time, PhantomJS was shipped with a rather outdated version of WebKit. As of v2.1.1 (macOS), Function.prototype.bind returns correct "length" of 1. Also works as expected in Safari 13.1 and r265666.