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Advantages of Antlr (versus say, lex/yacc/bison) [closed]
...as-is. To use ANTLR (or any other LL parser generator), you would need to convert this grammar to something that is not left-recursive. However, Bison has no problem with grammars of this form. You would need to declare '+' and '-' as left-associative operators, but that is not strictly required ...
Using ECMAScript 6
...s)
Using Babel in your development pipeline will automatically transpile (convert) your JavaScript to be cross-browser compatible. Or, if you're using TypeScript, you can rest easy; your code is already getting transpiled.
Don't want to setup a transpiler (such as Babel/Typescript), or do yo...
Any reason not to use '+' to concatenate two strings?
...e Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, but other implementations can't, so programmers are discouraged from relying on this.) ''.join is the right way t...
How to cast an object in Objective-C
... Great answer. You could make it a little clearer by breaking out the cast and assignment into two lines.
– Guido Anselmi
Jun 3 '14 at 21:06
1
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Is it possible to declare a variable in Gradle usable in Java?
... in Java ?
Basically I would like to declare some vars in the build.gradle and then getting it (obviously) at build time. Just like a pre-processor macros in C/C++...
...
CSS hexadecimal RGBA?
...and need to create CSS from it at runtime. This requires the extra step of converting from hex to decimal if you want to add alpha to it, which is clunky.
– Beejor
May 5 '15 at 15:17
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JavaScript checking for null vs. undefined and difference between == and ===
...perands are of different types, === will always return false while == will convert one or both operands into the same type using rules that lead to some slightly unintuitive behaviour. If the operands are of the same type (e.g. both are strings, such as in the typeof comparison above), == and === wi...
Iterate over model instance field names and values in template
...ts have changed slightly. A migration guide has been provided to assist in converting your code to use the new, official API.
In the below example, we will utilize the formalized method for retrieving all field instances of a model via Client._meta.get_fields():
fields = [(f.verbose_name, f.name) f...
What's the result of += in C and C++?
...
Semantics of the compound assignment operators is different in C and C++:
C99 standard, 6.5.16, part 3:
An assignment operator stores a value in the object designated by the left operand. An
assignment expression has the value of the left operand after the assignment, but is not an
...
Running bash script from within python
... subprocess.check_call("./script.sh '%s'" % arg, shell=True)
Remember to convert the args to string before passing, using str(arg).
This can be used to pass as many arguments as desired:
subprocess.check_call("./script.ksh %s %s %s" % (arg1, str(arg2), arg3), shell=True)
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