大约有 11,400 项符合查询结果（耗时：0.0321秒） [XML]
What does “fragment” mean in ANTLR?
...ent is somewhat akin to an inline function: It makes the grammar more readable and easier to maintain.
A fragment will never be counted as a token, it only serves to simplify a grammar.
Consider:
NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS;
fragment DIGITS: '1'..'9' '0'..'9'*;
fragment OCTAL_DIGIT...
How does a public key verify a signature?
I am trying to get a better grapple on how public/private keys work. I understand that a sender may add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
...
When to use the brace-enclosed initializer?
...n C++11, we have that new syntax for initializing classes which gives us a big number of possibilities how to initialize variables.
...
Is recursion ever faster than looping?
...sion is sometimes a lot cleaner than looping, and I'm not asking anything about when I should use recursion over iteration, I know there are lots of questions about that already.
...
Is calculating an MD5 hash less CPU intensive than SHA family functions?
...my Intel x86 (Core2 Quad Q6600, 2.4 GHz, using one core), I get this in 32-bit mode:
MD5 411
SHA-1 218
SHA-256 118
SHA-512 46
and this in 64-bit mode:
MD5 407
SHA-1 312
SHA-256 148
SHA-512 189
Figures are in megabytes per second, for a "long" message (this is what ...
Various ways to remove local Git changes
I just cloned a git repository and checked out a branch. I worked on it, and then decided to remove all my local changes, as I wanted the original copy.
...
How do servlets work? Instantiation, sessions, shared variables and multithreading
Suppose, I have a webserver which holds numerous servlets. For information passing among those servlets I am setting session and instance variables.
...
In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
I'm having a hard time wrapping my brain around PEP 380 .
8 Answers
8
...
Why doesn't C++ have a garbage collector?
I'm not asking this question because of the merits of garbage collection first of all. My main reason for asking this is that I do know that Bjarne Stroustrup has said that C++ will have a garbage collector at some point in time.
...
What new capabilities do user-defined literals add to C++?
...-defined literals which will allow the introduction of new literal syntax based on existing literals ( int , hex , string , float ) so that any type will be able to have a literal presentation.
...