JSLint报告意外使用“&”和“|” – 我想清理这个

我试图让我的Javascript代码100%JSLint干净。

我已经从其他地方提取了一些JS代码来创buildUUID。 该代码具有以下行:

s[16] = hexDigits.substr((s[16] & 0x3) | 0x8, 1); 

这一行煽动JSLint生成两个错误消息:

 1) Unexpected use of '&' 2) Unexpected use of '|' 

我不明白为什么 – 我会很感激有关如何重新编码以消除错误信息的忠告。

“为什么”的原因是实际的按位操作在JS中非常罕见,而出现在JS代码中的操作符几乎总是布尔版本( &&|| )的拼写错误。 这就是为什么JSLint关心。 这是一个按位运算的合法使用。 我相信你可以用这个bitwise标志来消除警告:

 /*jslint bitwise: true */ 

你有没有给它一个bitwise选项? 该选项会警告所有使用按位运算的情况,因为它们在Javascript中往往效率低下(本地浮点数需要转换为按位运算的整数,然后再转换回来)

如果您正在使用此JavaScript lint工具,则可以在命令行中指定一个configuration文件,以指定启用/禁用哪些检查。

例如,我通常会调用我的如下:

 jsl -conf jsl.conf 

用一个看起来像这样的jsl.conf文件

 #---------------------------------------------------------------------------- # # This is a slightly edited version of the jsl.default.conf file that comes # with the install package for JavaScript Lint. # #---------------------------------------------------------------------------- # # Configuration File for JavaScript Lint 0.3.0 # Developed by Matthias Miller (http://www.JavaScriptLint.com) # # This configuration file can be used to lint a collection of scripts, or to # enable or disable warnings for scripts that are linted via the command line. # ### Warnings # Enable or disable warnings based on requirements. # Use "+WarningName" to display or "-WarningName" to suppress. # -no_return_value # function {0} does not always return a value +duplicate_formal # duplicate formal argument {0} -equal_as_assign # test for equality (==) mistyped as assignment (=)?{0} +var_hides_arg # variable {0} hides argument -redeclared_var # redeclaration of {0} {1} -anon_no_return_value # anonymous function does not always return a value +missing_semicolon # missing semicolon +meaningless_block # meaningless block; curly braces have no impact +comma_separated_stmts # multiple statements separated by commas (use semicolons?) +unreachable_code # unreachable code -missing_break # missing break statement -missing_break_for_last_case # missing break statement for last case in switch -comparison_type_conv # comparisons against null, 0, true, false, or an empty string allowing implicit type conversion (use === or !==) -inc_dec_within_stmt # increment (++) and decrement (--) operators used as part of greater statement +useless_void # use of the void type may be unnecessary (void is always undefined) +multiple_plus_minus # unknown order of operations for successive plus (eg x+++y) or minus (eg x---y) signs +use_of_label # use of label -block_without_braces # block statement without curly braces -leading_decimal_point # leading decimal point may indicate a number or an object member +trailing_decimal_point # trailing decimal point may indicate a number or an object member -octal_number # leading zeros make an octal number +nested_comment # nested comment -misplaced_regex # regular expressions should be preceded by a left parenthesis, assignment, colon, or comma -ambiguous_newline # unexpected end of line; it is ambiguous whether these lines are part of the same statement -empty_statement # empty statement or extra semicolon -missing_option_explicit # the "option explicit" control comment is missing +partial_option_explicit # the "option explicit" control comment, if used, must be in the first script tag +dup_option_explicit # duplicate "option explicit" control comment +useless_assign # useless assignment -ambiguous_nested_stmt # block statements containing block statements should use curly braces to resolve ambiguity +ambiguous_else_stmt # the else statement could be matched with one of multiple if statements (use curly braces to indicate intent) -missing_default_case # missing default case in switch statement +duplicate_case_in_switch # duplicate case in switch statements +default_not_at_end # the default case is not at the end of the switch statement +legacy_cc_not_understood # couldn't understand control comment using /*@keyword@*/ syntax +jsl_cc_not_understood # couldn't understand control comment using /*jsl:keyword*/ syntax +useless_comparison # useless comparison; comparing identical expressions +with_statement # with statement hides undeclared variables; use temporary variable instead +trailing_comma_in_array # extra comma is not recommended in array initializers +assign_to_function_call # assignment to a function call -parseint_missing_radix # parseInt missing radix parameter ### Output format # Customize the format of the error message. # __FILE__ indicates current file path # __FILENAME__ indicates current file name # __LINE__ indicates current line # __ERROR__ indicates error message # # Visual Studio syntax (default): +output-format __FILE__(__LINE__): __ERROR__ # Alternative syntax: #+output-format __FILE__:__LINE__: __ERROR__ ### Context # Show the in-line position of the error. # Use "+context" to display or "-context" to suppress. # +context ### Semicolons # By default, assignments of an anonymous function to a variable or # property (such as a function prototype) must be followed by a semicolon. # +lambda_assign_requires_semicolon ### Control Comments # Both JavaScript Lint and the JScript interpreter confuse each other with the syntax for # the /*@keyword@*/ control comments and JScript conditional comments. (The latter is # enabled in JScript with @cc_on@). The /*jsl:keyword*/ syntax is preferred for this reason, # although legacy control comments are enabled by default for backward compatibility. # #+legacy_control_comments ### JScript Function Extensions # JScript allows member functions to be defined like this: # function MyObj() { /*constructor*/ } # function MyObj.prototype.go() { /*member function*/ } # # It also allows events to be attached like this: # function window::onload() { /*init page*/ } # # This is a Microsoft-only JavaScript extension. Enable this setting to allow them. # -jscript_function_extensions ### Defining identifiers # By default, "option explicit" is enabled on a per-file basis. # To enable this for all files, use "+always_use_option_explicit" -always_use_option_explicit # Define certain identifiers of which the lint is not aware. # (Use this in conjunction with the "undeclared identifier" warning.) # # Common uses for webpages might be: #+define window #+define document ### Interactive # Prompt for a keystroke before exiting. #+pauseatend ### Files # Specify which files to lint # Use "+recurse" to enable recursion (disabled by default). # To add a set of files, use "+process FileName", "+process Folder\Path\*.js", # or "+process Folder\Path\*.htm". # 

PS检查出我的JavaScript UUID页面 ,顺便说一下,通过了所有上面的JSLint检查。 🙂