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How can I compare two lists in python and return matches
... answer is more flexible and readable, since people may need difference or union.
– Shihe Zhang
Nov 1 '17 at 2:31
What...
What is the fastest or most elegant way to compute a set difference using Javascript arrays?
...
Why JavaScript sets don't have union/intersect/difference built in is beyond me...
– SwiftsNamesake
Nov 27 '16 at 4:50
6
...
What is 'Pattern Matching' in functional languages?
...e functional languages allow you define simple data types called "disjoint unions" or "algebraic data types". These data structures are simple containers, and can be recursively defined. For example:
type 'a list =
| Nil
| Cons of 'a * 'a list
defines a stack-like data structure. Think of...
__attribute__ - C/C++ - 清泛网 - 专注C/C++及内核技术
...nocommon,deprecated,mode,section,shared, tls_model,transparent_union,unused,vector_size,weak,dllimport,dlexport等,
详细信息可参考:
http://gcc.gnu.org/onlinedocs/gcc-4.0.0/gcc/Variable-Attributes.html#Variable-Attributes
类型属性(Type Attribute)
关键...
C/C++ Struct vs Class
...long ago, back when C++ was still known as "C with Classes."
Note that C unions work with C++, but not the other way around. For example
union WorksWithCppOnly{
WorksWithCppOnly():a(0){}
friend class FloatAccessor;
int a;
private:
float b;
};
And likewise
typedef union friend{...
How to prevent ifelse() from turning Date objects into numeric objects
... My vote would be for a factor return object that had levels that were the union of the levels of true's and false's levels.
– IRTFM
Aug 28 '16 at 20:05
3
...
How to use NULL or empty string in SQL
...ERE SomeCol = '' OR SomeCol IS NULL;
SELECT *
FROM #T
WHERE SomeCol = ''
UNION ALL
SELECT *
FROM #T
WHERE SomeCol IS NULL;
SELECT *
FROM #T
WHERE EXISTS ((SELECT NULL UNION SELECT '') INTERSECT SELECT SomeCol);
And some non-sargable ones...
SELECT *
FROM #T
WHERE IIF(SomeCol <> '',0,1) ...
String.Join method that ignores empty strings?
...earchTerm1, N'') AS RPT_SearchTerm, 1 AS RPT_Sort
UNION ALL SELECT NULLIF(@in_SearchTerm2, N'') AS RPT_SearchTerm, 2 AS RPT_Sort
UNION ALL SELECT NULLIF(@in_SearchTerm3, N'') AS RPT_SearchTerm, 3 AS RPT_Sort
UNION ALL SELECT...
Is there any difference between GROUP BY and DISTINCT
... 12 there do appear to be cases where DISTINCT, getting distinct values by UNION, and GROUP BY work differently. I just had a case earlier today where DISTINCT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I...
Enforcing the type of the indexed members of a Typescript object?
... a similar syntax to enforce that an object has a key for every entry in a union type:
type DayOfTheWeek = "sunday" | "monday" | "tuesday" | "wednesday" | "thursday" | "friday" | "saturday";
type ChoresMap = { [day in DayOfTheWeek]: string };
const chores: ChoresMap = { // ERROR! Property 'saturd...