brackets

different meanings of brackets in python

非 Y 不嫁゛ 提交于 2019-11-27 06:55:39
I am curious, what do the 3 different brackets mean in python programming? Not sure if i'm correct about this, but please correct me if i'm wrong. [] - # Normally used for dictionaries, list items () - # Used to identify params {} - # I have no idea what this does... Or if these brackets can be used for other purposes, any advises are welcomed! Thanks! [] : Used to define mutable data types - lists, list comprehensions and for indexing/lookup/slicing. () : Define tuples, order of operations, generator expressions, function calls and other syntax. {} : The two hash table types - dictionaries

Automatic closing brackets for Vim [closed]

大兔子大兔子 提交于 2019-11-27 06:37:40
Is there any WORKING plugin for Vim 7.4 that would automatically close brackets ('{}', '[]', '()') and maybe insert some carriage returns (for '{}' at least)? I know this question has been asked quite a few times but none of the answers either do not seem to work in vim 7.4 or the plugin has not been updated or something. So far I've tried vim-smartinput, autoclose and delimitmate and NONE of these have managed to insert any closing characters even though I have enabled the plugins and they otherwise seem to be active. I don't know if there has been some changes in vim that somehow breaks

Can I use Perl regular expressions to match balanced text?

风格不统一 提交于 2019-11-27 05:04:34
I would like to match text enclosed in brackets etc in Perl. How can I do that? This is a question from the official perlfaq . We're importing the perlfaq to Stack Overflow . This is the official FAQ answer minus any subsequent edits. Your first try should probably be the Text::Balanced module, which is in the Perl standard library since Perl 5.8. It has a variety of functions to deal with tricky text. The Regexp::Common module can also help by providing canned patterns you can use. As of Perl 5.10, you can match balanced text with regular expressions using recursive patterns. Before Perl 5.10

Extracting string from within round brackets in Java with regex

最后都变了- 提交于 2019-11-26 22:11:58
问题 I'm trying to extract a string from round brackets. Let's say, I have John Doe (123456789) and I want to output the string 123456789 only. I have found this link and this regex: /\(([^)]+)\)/g However, I wasn't able to figure out how to get the wanted result. Any help would be appreciated. Thanks! 回答1: String str="John Doe (123456789)"; System.out.println(str.substring(str.indexOf("(")+1,str.indexOf(")"))); Here I'm performing string operations. I'm not that much familiar with regex. 回答2: You

Replace string between square brackets with sed

一个人想着一个人 提交于 2019-11-26 22:07:24
问题 I have some strings in a textfile that look like this: [img:3gso40ßf] I want to replace them to look like normal BBCode: [img] How can I do that with sed? I tried this one but it doesn't do anything: sed -i 's/^[img:.*]/[img]/g' file.txt 回答1: Escape those square brackets Square brackets are metacharacters: they have a special meaning in POSIX regular expressions. If you mean [ and ] literally , you need to escape those characters in your regexp: $ sed -i .bak 's/\[img:.*\]/\[img\]/g' file.txt

PHP conditionals, brackets needed?

微笑、不失礼 提交于 2019-11-26 21:56:53
I was just browsing a forum and someone asked about a PHP file they had found on the web. It has several spots like this in the code: if ($REMOTE_ADDR == "") $ip = "no ip"; else $ip = getHostByAddr($REMOTE_ADDR); I have always thought brackets are needed to enclose what you want to do if the condition is true. Is there some other alternative, such as if it is on the same line you don't? There is also another line like this: if ($action != ""): mail("$adminaddress","Visitor Comment from YOUR SITE", My instinct is to say this wouldn't work, but I also don't know if it is an outdated PHP file and

What does enclosing a class in angle brackets “<>” mean in TypeScript?

风流意气都作罢 提交于 2019-11-26 19:57:09
问题 I am very new to TypeScript and I am loving it a lot, especially how easy it is to do OOP in Javascript. I am however stuck on trying to figure out the semantics when it comes to using angle brackets. From their docs, I have seen several example like interface Counter { (start: number): string; interval: number; reset(): void; } function getCounter(): Counter { let counter = <Counter>function (start: number) { }; counter.interval = 123; counter.reset = function () { }; return counter; } and

How to use double brackets in a regular expression?

醉酒当歌 提交于 2019-11-26 17:24:42
问题 What do double square brackets mean in a regex? I am confused about the following examples: /[[^abc]]/ /[^abc]/ I was testing using Rubular, but I didn't see any difference between the one with double brackets and single brackets. 回答1: Posix character classes use a [:alpha:] notation, which are used inside a regular expression like: /[[:alpha:][:digit:]]/ You'll need to scroll down a ways to get to the Posix information in the link above. From the docs: POSIX bracket expressions are also

what is [] brackets in .net? [duplicate]

◇◆丶佛笑我妖孽 提交于 2019-11-26 16:15:54
问题 This question already has answers here : All possible array initialization syntaxes (13 answers) Closed 6 years ago . i have seen [] such brackets in c# very very rarely but when i start to learn asp.net i have seen them many times but still i couldn't understand what they does ? They are not part of code as using for arrays.For example [webmethods] which is just over the methods or there are some over classes. Are they part of .net or they are just tell something to CLR ? or ? 回答1: They are

different meanings of brackets in python

烈酒焚心 提交于 2019-11-26 15:36:08
问题 I am curious, what do the 3 different brackets mean in python programming? Not sure if i'm correct about this, but please correct me if i'm wrong. [] - # Normally used for dictionaries, list items () - # Used to identify params {} - # I have no idea what this does... Or if these brackets can be used for other purposes, any advises are welcomed! Thanks! 回答1: [] : Used to define mutable data types - lists, list comprehensions and for indexing/lookup/slicing. () : Define tuples, order of