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How can I remove a character from a string using Javascript?
...y
tmp.splice(i - 1 , 1); // remove 1 element from the array (adjusting for non-zero-indexed counts)
return tmp.join(''); // reconstruct the string
}
console.log("crt/r2002_2".removeCharAt(4));
Since user1293504 used the normal count instead of a zero-indexed count, we've got to remove 1 f...
CoffeeScript, When to use fat arrow (=>) over arrow (->) and vice versa
...
No, that's not the rule I would use.
The major use-case I've found for the fat-arrow in defining methods is when you want to use a method as a callback and that method references instance fields:
class A
constructor: (@msg) ->
thin: -> alert @msg
fat: => alert @msg
x = new ...
How to create a MySQL hierarchical recursive query
...
For MySQL 8+: use the recursive with syntax.
For MySQL 5.x: use inline variables, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
...
How to empty a list?
...Here's an example:
lst1 = [1, 2, 3]
lst2 = lst1
del lst1[:]
print(lst2)
For the sake of completeness, the slice assignment has the same effect:
lst[:] = []
It can also be used to shrink a part of the list while replacing a part at the same time (but that is out of the scope of the question).
...
How to access property of anonymous type in C#?
...et a value:
object v = p.GetValue(o, null);
This answer is long overdue for an update for C# 4:
dynamic d = o;
object v = d.Foo;
And now another alternative in C# 6:
object v = o?.GetType().GetProperty("Foo")?.GetValue(o, null);
Note that by using ?. we cause the resulting v to be null in t...
Django-Admin: CharField as TextArea
...
You will have to create a forms.ModelForm that will describe how you want the descr field to be displayed, and then tell admin.ModelAdmin to use that form. For example:
from django import forms
class CabModelForm( forms.ModelForm ):
descr = forms...
Match whitespace but not newlines
...t matches these characters
U+000A LINE FEED
U+000B LINE TABULATION
U+000C FORM FEED
U+000D CARRIAGE RETURN
U+0085 NEXT LINE (not matched by \s)
U+2028 LINE SEPARATOR
U+2029 PARAGRAPH SEPARATOR
There are seven vertical whitespace characters which match \v and eighteen horizontal ones which match ...
Servlet for serving static content
...on two different containers (Tomcat and Jetty), but their default servlets for serving the static content have a different way of handling the URL structure I want to use ( details ).
...
How do I calculate tables size in Oracle
...ght be interested in this query. It tells you how much space is allocated for each table taking into account the indexes and any LOBs on the table. Often you are interested to know "How much spaces the the Purchase Order table take, including any indexes" rather than just the table itself. You ca...
How to delete migration files in Rails 3
...
I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the last one),...