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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...parameter is a positional parameter with more than one digit…
Let's test:
$ set -- {0..100}
$ echo $22
12
$ echo ${22}
20
Huh. Neat. I honestly didn't know that before writing this (I've never had more than 9 positional parameters before.)
Of course, you also need braces to do the powerfu...
Fastest Way of Inserting in Entity Framework
I'm looking for the fastest way of inserting into Entity Framework.
30 Answers
30
...
Open a URL in a new tab (and not a new window)
...the default user preference in most browsers is for new tabs, so a trivial test on a browser where that preference hasn't been changed will not demonstrate this.)
CSS3 proposed target-new, but the specification was abandoned.
The reverse is not true; by specifying dimensions for the window in the ...
How to have conditional elements and keep DRY with Facebook React's JSX?
...r If = React.createClass({
render: function() {
if (this.props.test) {
return this.props.children;
}
else {
return false;
}
}
});
And use it this way:
render: function () {
return (
<div id="page">
<I...
Java 8: Lambda-Streams, Filter by Method with Exception
...er examples on how to use it (after statically importing UtilException):
@Test
public void test_Consumer_with_checked_exceptions() throws IllegalAccessException {
Stream.of("java.lang.Object", "java.lang.Integer", "java.lang.String")
.forEach(rethrowConsumer(className -> System.out...
How to match “any character” in regular expression?
...
There are lots of sophisticated regex testing and development tools, but if you just want a simple test harness in Java, here's one for you to play with:
String[] tests = {
"AAA123",
"ABCDEFGH123",
"XXXX123",
"XYZ123ABC",
...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
...QL and index that table and it's entries.
1.Table Structure
CREATE TABLE test_solr_mysql
(
id INT UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(45) NULL,
created TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (id)
);
2.Populate the above table
INSERT INTO `test_solr_mysql` (`n...
How do you use script variables in psql?
...ontrary to Bryce's report, it seems to work fine for me. CREATE TABLE test (name VARCHAR, age INT); INSERT INTO test (name, age) VALUES ('Jack', 21), ('Jill', 20); WITH vars AS (SELECT N'Jack' AS name, 21 AS age) SELECT test.* FROM test, vars WHERE test.name = vars.name and te...
How to explain dependency injection to a 5-year-old? [closed]
...ing this way becomes problematic especially when you want to perform unit testing.
The main problem comes when you need to test one particular object, you need to create an instance of other object, and most likely you need to create an instance of yet other object to do that. The chain may become...
How to model type-safe enum types?
...rgumentException
}
// At REPL:
scala> val a = unitMatrixInt(3)
a: teste7.MatrixInt =
/ 1 0 0 \
| 0 1 0 |
\ 0 0 1 /
scala> a('row, 1) = a.row(0)
res41: teste7.MatrixInt =
/ 1 0 0 \
| 1 0 0 |
\ 0 0 1 /
scala> a('column, 2) = a.row(0)
res42: teste7.MatrixInt =
/ 1 0 1 \
| 0 1 0 |
\ 0 0...