大约有 3,000 项符合查询结果(耗时:0.0256秒) [XML]

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Why is whitespace sometimes needed around metacharacters?

... There is a list of characters that separate tokens in BASH. These characters are called metacharacters and they are |, &, ;, (, ), <, >, space and tab. On the other hand, curly braces ({ and }) are just ordinary characters that make up words. Omitting the se...
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Allow CORS REST request to a Express/Node.js application on Heroku

...problem and the solution was not related to CORS. Turns out that JSON Web Token secret string was not defined in the environment variables, so the token could not be signed. This caused to any POST request that relies on checking or signing a token to get a timeout and return a 503 error, telling t...
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A Windows equivalent of the Unix tail command [closed]

...cefile=%3 rem *** Get the current line count of file *** FOR /F "usebackq tokens=3,3 delims= " %%l IN (`find /c /v "" %sourcefile%`) DO (call SET find_lc=%%l) rem *** Calculate the lines to skip SET /A skiplines=%find_lc%-!skiplines! rem *** Display to screen line needed more +%skiplines% %source...
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Symfony 2: How do I check if a user is not logged in inside a template?

...s it results in the following error: No Authentication Provider found for token of class "Symfony\Component\Security\Core\Authentication\Token\PreAuthenticatedToken". – Harold Jun 20 '14 at 10:26 ...
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How can I detect the touch event of an UIImageView?

...in your .m file: UITapGestureRecognizer *newTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myTapMethod)]; [myImageView setUserInteractionEnabled:YES]; [myImageView addGestureRecognizer:newTap]; -(void)myTapMethod{ // Treat image tap } ...
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Easy way to concatenate two byte arrays

... is using java.nio.ByteBuffer. Something like ByteBuffer bb = ByteBuffer.allocate(a.length + b.length + c.length); bb.put(a); bb.put(b); bb.put(c); byte[] result = bb.array(); // or using method chaining: byte[] result = ByteBuffer .allocate(a.length + b.length + c.length) .put(a...
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Nullable vs. int? - Is there any difference?

...hat in the parsing phase after an is (or an as) operator, when we face a ? token we check if the next token can be interpreted as a unary operator (& could be one) and if so: the parser doesn't care about the possibility of the ? token being a type modifier, it simply uses the type before it, an...
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What's the algorithm to calculate aspect ratio?

...1% (w x h prevalence% change%) def __init__(self, steam_line): tokens = steam_line.split(' ') self.width = int(tokens[0]) self.height = int(tokens[2]) self.prevalence = float(tokens[3].replace('%', '')) # This part based on pixdiablo's gcd answer - http:...
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R memory management / cannot allocate vector of size n Mb

...at is not a cure in general -- I've switched, and now I have Error: cannot allocate vector of size ... Gb instead (but yeah, I have a lot of data). – om-nom-nom Apr 11 '12 at 17:20 ...
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Why aren't variable-length arrays part of the C++ standard?

...ite the same, as it uses dynamic memory, and making it use one's own stack-allocator isn't exactly easy (alignment is an issue, too). It also doesn't solve the same problem, because a vector is a resizable container, whereas VLAs are fixed-size. The C++ Dynamic Array proposal is intended to introduc...