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Can we omit parentheses when creating an object using the “new” operator?
...nt precedence. According to MDN the part of JavaScript operator precedence table we are interested in looks like:
╔════════════╦═════════════════════════════╦═══════════════╦═...
How to do associative array/hashing in JavaScript
...ash/AS3 Dictionary does. In JavaScript, var obj1 = {}; var obj2 = {}; var table= {}; table[obj1] = "A"; table[obj2] = "B"; alert(table[obj1]); //displays B, because it can't differentiate between keys obj1 and obj2; they're both converted to string and just become something like "Object". Total fa...
How can I combine multiple rows into a comma-delimited list in Oracle? [duplicate]
...
Here is a simple way without stragg or creating a function.
create table countries ( country_name varchar2 (100));
insert into countries values ('Albania');
insert into countries values ('Andorra');
insert into countries values ('Antigua');
SELECT SUBSTR (SYS_CONNECT_BY_PATH (country_na...
Is it possible to modify variable in python that is in outer, but not global, scope?
...esides the global
(module) scope.
For python 2, I usually just use a mutable object (like a list, or dict), and mutate the value instead of reassign.
example:
def foo():
a = []
def bar():
a.append(1)
bar()
bar()
print a
foo()
Outputs:
[1, 1]
...
Is null an Object?
...y hands with »Big Apple« (=reference type name) written on it.
There's a table (=heap) in front of me.
If there is an apple (=instance) on the table there is a cord (=reference) connected to it.
I hold the other end of this cord in my hand (=reference variable) .
I trace the apple along the cord...
How to overload functions in javascript?
...he second argument, it would have to be passed as null (or some other detectable value) instead and your code would detect that:
obj.query("firstArg", null, "thirdArg");
Here's a jQuery example of optional arguments. both arguments are optional and take on default values if not passed:
clone:...
What’s the difference between ScalaTest and Scala Specs unit test frameworks?
...
Mockito has been given a nice BDD support in specs: Mockito
specs has DataTables which allow to group a lot of small example in a sort of table (if you can stand operators being used as the table delimiters)
In specs, you can define examples which are nested as libidum and automatically cleaned-up ...
How to store a dataframe using Pandas
...and read_pickle respectively).
Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:
store = HDFStore('store.h5')
store['df'] = df # save it
store['df'] # load it
More advanced strategies are discussed in the cookbook.
Since 0.13 there's...
SQL Server IN vs. EXISTS Performance
... test case does not mean that the optimizer will do the exact same plan on tables with different statistics. This might lead someone to think the answer is partial - but the nonexistence of multiple semijoin operators is fact. Maybe I'll find a list somewhere and link it.
– Geo...
What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]
...storing only one copy
of each distinct string value, which
must be immutable. Interning strings
makes some string processing tasks
more time- or space-efficient at the
cost of requiring more time when the
string is created or interned. The
distinct values are stored in a string
inter...