reserved-words

问题 If I don't use let or var before allocation to my varaiable name I get a TypeError: name.map is not a function Is name a reserved word or anything else. If so I'm wondering why I don't get any error at the allocation name = [ ... ]; Can anybody give me some more information about this behaviour. name = ["apple", "orange", "strawberry", "banana"]; result = name.map(elem => elem.toUpperCase() ); console.log(result); If I put let or var before it works as desired. let name = ["apple", "orange",

问题 Consider following program: #include <cstdio> int main() { int printf=9; std::printf("%d",printf); } Is it fine to use built in function name as an identifier in variable declaration? Is this well defined program? I mean is behaviour of above program well defined? I am curious to know whether the C++ standard allows to use standard function names as identifiers of variables 回答1: It's well-formed because neither std::printf nor ::printf (which may also have been declared by <cstdio> !) are

问题 Consider following program: #include <cstdio> int main() { int printf=9; std::printf("%d",printf); } Is it fine to use built in function name as an identifier in variable declaration? Is this well defined program? I mean is behaviour of above program well defined? I am curious to know whether the C++ standard allows to use standard function names as identifiers of variables 回答1: It's well-formed because neither std::printf nor ::printf (which may also have been declared by <cstdio> !) are

问题 I understand that in C++ double underscores in identifiers are reserved for the compiler. I have some C code which has characteristics similar to this in the corresponding header files: extern "C" { #define HELLO__THERE 1 int hello__out__there( int ); } I will be using this header in a C++ project, and plan to be doing things in C++ like: if (HELLO__THERE == abc) hello__out__there(foo); Is this acceptable behavior in C++, covered by the standard? 回答1: double underlines in identifiers are

问题 It seems reserved words can not be used as attributes in python: $ python Python 3.6.2 |Continuum Analytics, Inc.| (default, Jul 20 2017, 13:51:32) [GCC 4.4.7 20120313 (Red Hat 4.4.7-1)] on linux Type "help", "copyright", "credits" or "license" for more information. >>> class A: >>> global = 3 File "<stdin>", line 2 global = 3 ^ SyntaxError: invalid syntax This seems sensible, since it is ambiguous: am I using the global keyword here? Difficult to say. But this is not sensible imho: >>> class

问题 I'm looking for a way to retrieve all the saved keywords in Java into some kind of data structure. For example: "for, while, if, else, int, double, etc." I need to do a name validation on a string, to be specific, I need to make sure it does not equal to any java keywords. Is there a specific way of retrieving all the keywords into one data structure? or do I need to just build a regex string with all these keywords in it : "for|while|if|..." and try and match my string against it? Thanks 回答1

问题 Is there some function for checking whether a word is reserved in PHP or I can use it myself? I can check it manually: just use it and see the error or warning, but I need to automate this check. Is there any way to do this? 回答1: Array borrowed from http://www.php.net/manual/en/reserved.keywords.php You could easily modify it to work for the predefined constants array. This works. <?php $keywords = array('__halt_compiler', 'abstract', 'and', 'array', 'as', 'break', 'callable', 'case', 'catch'

问题 Is there a good, authoritative list of reserved words for RAILS-3? Candidates: http://oldwiki.rubyonrails.org/rails/pages/ReservedWords, but it seems a bit out of date and rails2. http://cheat.errtheblog.com/s/rails_reserved_words (but there seems no authority to this - it could just grow and grow...) http://latheesh.com/2010/02/02/rails-reserved-words/ Background: I'm maintaining a long-serving rails app and it has plenty of usages of reserved words (judging that http://oldwiki.rubyonrails

问题 Is there a good, authoritative list of reserved words for RAILS-3? Candidates: http://oldwiki.rubyonrails.org/rails/pages/ReservedWords, but it seems a bit out of date and rails2. http://cheat.errtheblog.com/s/rails_reserved_words (but there seems no authority to this - it could just grow and grow...) http://latheesh.com/2010/02/02/rails-reserved-words/ Background: I'm maintaining a long-serving rails app and it has plenty of usages of reserved words (judging that http://oldwiki.rubyonrails

问题 Closed . This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 5 years ago . I'm referring to MDN's article on JavaScript's 'future reserved words' (for use in the new strict mode) - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#Future_reserved_keywords . All the reserved words indicate that JavaScript will possibly