This page tests toString conversion of RegExp objects, particularly wrt to '/' characters and RegExp.prototype. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS RegExp('/').source is "\\/" PASS RegExp('').source is "(?:)" PASS RegExp.prototype.source is "(?:)" PASS RegExp('/').toString() is "/\\//" PASS RegExp('').toString() is "/(?:)/" PASS RegExp.prototype.toString() is "/(?:)/" PASS testForwardSlash("^/$", "/"); is true PASS testForwardSlash("^/$", "/"); is true PASS testForwardSlash("^\/$", "/"); is true PASS testForwardSlash("^\\/$", "\/"); is true PASS testForwardSlash("^\\\/$", "\/"); is true PASS testForwardSlash("^\\\\/$", "\\/"); is true PASS testForwardSlash("^\\\\\/$", "\\/"); is true PASS testForwardSlash("x/x/x", "x\/x\/x"); is true PASS testForwardSlash("x\/x/x", "x\/x\/x"); is true PASS testForwardSlash("x/x\/x", "x\/x\/x"); is true PASS testForwardSlash("x\/x\/x", "x\/x\/x"); is true PASS testLineTerminator("\n"); is false PASS testLineTerminator("\\n"); is false PASS testLineTerminator("\r"); is false PASS testLineTerminator("\\r"); is false PASS testLineTerminator("\u2028"); is false PASS testLineTerminator("\\u2028"); is false PASS testLineTerminator("\u2029"); is false PASS testLineTerminator("\\u2029"); is false PASS RegExp('[/]').source is '[/]' PASS RegExp('\\[/]').source is '\\[\\/]' PASS var o = new RegExp(); o.toString() === '/'+o.source+'/' && eval(o.toString()+'.exec(String())') is [""] PASS successfullyParsed is true TEST COMPLETE