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How to model type-safe enum types?
...d, which does not have the problems Schildmeijer mentioned. So do "object foo extends App { ... }" And you have immediate access to command-line arguments through the args variable.
– AmigoNico
Jul 25 '12 at 2:55
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R: Comment out block of code [duplicate]
...just put # signs in front of every line (possibly with editor shortcuts).
foo <- scan(what="character")
These are comments
These are still comments
Can also be code:
x <- 1:10
One line must be blank
rm(foo)
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How to set child process' environment variable in Makefile
...st pointed out, you can export individual variables with:
export MY_VAR = foo # Available for all targets
Or export variables for a specific target (target-specific variables):
my-target: export MY_VAR_1 = foo
my-target: export MY_VAR_2 = bar
my-target: export MY_VAR_3 = baz
my-target: depende...
How do you tell someone they're writing bad code? [closed]
...s better than cutting & pasting.
Explain why an array is better than $foo1, $foo2, $foo3.
Explain why global variables are dangerous, and that local variables will make life easier.
Simply whipping out a coding standard and saying "do this" is worthless because it doesn't explain to the progr...
Checking that a List is not empty in Hamcrest
...;
E.g. if you run
assertEquals(new ArrayList<>(0), Arrays.asList("foo", "bar");
you get
java.lang.AssertionError
Expected :[]
Actual :[foo, bar]
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Checking length of dictionary object [duplicate]
...setting 0 on the object, or are you relying on custom string keys? eg obj['foo'] = 'bar';. If the latter, again, why the need for length?
Edit #1: Why can't you just do this?
list = [ {name:'john'}, {name:'bob'} ];
Then iterate over list? The length is already set.
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Unpacking array into separate variables in JavaScript
...two = arr[1];
ES6 will allow destructuring assignment:
let [x, y] = ['foo', 'bar'];
console.log(x); // 'foo'
console.log(y); // 'bar'
Or, to stick to your initial example:
var arr = ['one', 'two'];
var [one, two] = arr;
You could also create a default value:
const [one = 'one', two = 'two...
How do I call one constructor from another in Java?
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Yes, it is possible:
public class Foo {
private int x;
public Foo() {
this(1);
}
public Foo(int x) {
this.x = x;
}
}
To chain to a particular superclass constructor instead of one in the same class, use super instead of...
How do I use arrays in C++?
...
Might be worth it to add a note that even tho in void foo(int a[3]) a does look like one is passing the array by value, modifying a inside of foo will modify the original array. This should be clear because arrays cannot be copied, but it might be worth it to reinforce that.
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How to drop columns by name in a data frame
...t) %in% c("z","u"))] ## works as expected
dat[ , -which(names(dat) %in% c("foo","bar"))] ## deletes all columns! Probably not what you wanted...
Instead use subset or the ! function:
dat[ , !names(dat) %in% c("z","u")] ## works as expected
dat[ , !names(dat) %in% c("foo","bar")] ## returns the un...