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What is a higher kinded type in Scala?
...va 5 generics are first-order.
The first-order interpretation of the above characterizations of abstractions are:
A type constructor is a type that you can apply to proper type arguments to "construct" a proper type.
A value constructor is a value that you can apply to proper value arguments to "co...
1052: Column 'id' in field list is ambiguous
...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
C/C++ Struct vs Class
...bjects. X AVOID defining a struct unless the type has all of the following characteristics: 1. It logically represents a single value, similar to primitive types (int, double, etc.). 2. It has an instance size under 16 bytes. 3. It is immutable.
– Abhijeet
De...
Working with select using AngularJS's ng-options
...o work... note the ng-model="blah" which is saying "set $scope.blah to the selected value".
Try this:
<select ng-model="blah" ng-options="item.ID as item.Title for item in items"></select>
Here's more from AngularJS's documentation (if you haven't seen it):
for array data sources...
Define variable to use with IN operator (T-SQL)
... VALUES (2)
INSERT INTO @MyList VALUES (3)
INSERT INTO @MyList VALUES (4)
SELECT *
FROM MyTable
WHERE MyColumn IN (SELECT Value FROM @MyList)
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Javascript seconds to minutes and seconds
... ... modify (9<s?':':':0') to (10>s?':0':':') (adding 1 char but 'sacrificing' 5 out of 6 true-paths to false-paths) OR (10<=s?':':':0') (adding 2 chars but maintaining 5 out of 6 true paths). Then I advise to change that final trailing +s to +(s|0) instead of Math.floor(s), as...
Typedef function pointer?
...ld use the original type, for instance
typedef int myinteger;
typedef char *mystring;
typedef void (*myfunc)();
using them like
myinteger i; // is equivalent to int i;
mystring s; // is the same as char *s;
myfunc f; // compile equally as void (*f)();
As you can ...
You can't specify target table for update in FROM clause
...llow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't reference that table in an inner query (you can however reference a field from that outer table...)
Th...
What does static_assert do, and what would you use it for?
...ou can put a static assert like this
static_assert(sizeof(unsigned int) * CHAR_BIT == 32);
in your code. On another platform, with differently sized unsigned int type the compilation will fail, thus drawing attention of the developer to the problematic portion of the code and advising them to re-...
SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...