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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 ...
Hide grid row in WPF
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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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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
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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...
System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()
...ost efficient since it does not even create an object, but new Date() is really just a thin wrapper about a long, so it is not far behind. Calendar, on the other hand, is relatively slow and very complex, since it has to deal with the considerably complexity and all the oddities that are inherent to...
How to get value of selected radio button?
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@mzalazar No, every radio-button has its own ID but all have the same name which is what puts them into one group so if you select one the other one gets deselected. With Kamran Ahmed answer you can check which of the radio buttons in the group is selected and get only the val...
Why do I get “Pickle - EOFError: Ran out of input” reading an empty file?
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catching an EOF exception won't save you from all the other potential errors.
– Padraic Cunningham
Jul 16 '14 at 23:06
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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:
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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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“Debug certificate expired” error in Eclipse Android plugins
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Upon installation, the Android SDK generates a debug signing certificate for you in a keystore called debug.keystore. The Eclipse plug-in uses this certificate to sign each application build that is generated.
Unfortunately a debug ...