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ANTLR: Is there a simple example?
...r, and evaluator using ANTLR4.
You first create a grammar. Below is a small grammar that you can use to evaluate expressions that are built using the 4 basic math operators: +, -, * and /. You can also group expressions using parenthesis.
Note that this grammar is just a very basic one: it does ...
Why doesn't os.path.join() work in this case?
... the Python docs for os.path.join:
If a component is an absolute path, all previous components are thrown away and joining continues from the absolute path component.
Note on Windows, the behaviour in relation to drive letters, which seems to have changed compared to earlier Python versions:
...
Another Repeated column in mapping for entity error
Despite all of the others post, I can't find a solution for this error with GlassFish, on MacOSX, NetBeans 7.2.
8 Answers
...
JavaScript checking for null vs. undefined and difference between == and ===
...is the difference between the null and undefined?
They're both values usually used to indicate the absence of something. undefined is the more generic one, used as the default value of variables until they're assigned some other value, as the value of function arguments that weren't provided when ...
Linear Regression and group by in R
...
fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) year
CA -1.34420990 0.17139963
NY 0.00196176 -0.01852429
Degrees of freedom: 20 total; 16 residual
Residual standard error: 0.820...
Manually adding a Userscript to Google Chrome
Instead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
...
How to change navbar collapse threshold using Twitter bootstrap-responsive?
... I can't think of any way to achieve the overriding without restating all the CSS declarations.
– methodofaction
Feb 23 '12 at 5:15
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Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
... the following way:
First take 2 variables: COUNTER and VALUE.
First set all registers to 0;
Every time you receive an integer I, increment COUNTER and set VALUE to max(VALUE, I);
Then send an ICMP echo request packet with data set to I to the router. Erase I and repeat.
Every time you receive the...
Hide grid row in WPF
...
UpVoted - Converters permit all this to be declarative in Xaml. I generally hate using code-behind to fiddle with visual stuff.
– Allen
May 22 '14 at 13:43
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Should 'using' directives be inside or outside the namespace?
...
There is actually a (subtle) difference between the two. Imagine you have the following code in File1.cs:
// File1.cs
using System;
namespace Outer.Inner
{
class Foo
{
static void Bar()
{
double d = Ma...