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Change default primary key in Eloquent
...gusflyer You are kidding right ? More than one primary key in one database table?
– Novica89
Oct 1 '14 at 10:39
@bagus...
Is the order of iterating through std::map known (and guaranteed by the standard)?
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std::map is a sorted associative container
std::unordered_map is a hash-table based associative container introduced in C++11
So, in order to clarify the guarantees on ordering.
In C++03:
std::set, std::multiset, std::map and std::multimap are guaranteed to be ordered according to the keys (...
switch / pattern matching idea
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The notable difference here between C# and F# is completeness of the pattern match. That the pattern match covers every possible case available, fully described, warnings from the compiler if you do not. While you can rightfully ar...
Is it possible to set a number to NaN or infinity?
...'t standard-library but a very common third-party library).
The following table summarizes the ways how one can create a not-a-number or a positive or negative infinity float:
╒══════════╤══════════════╤═════════════...
Seeding the random number generator in Javascript
...334677,s)>>>0)/2**32;
These LCG values are from: P. L'Ecuyer: A table of Linear Congruential Generators of different sizes and good lattice structure, April 30 1997.
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How to count occurrences of a column value efficiently in SQL?
I have a table of students:
6 Answers
6
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Double exclamation points? [duplicate]
... then it may not be 0 but some other falsy value. See the following truth table:
Truth Table for javascript
'' == '0' // false
0 == '' // true
0 == '0' // true
false == 'false' // false
false == '0' // true
fa...
ASP.NET MVC 404 Error Handling [duplicate]
...enerated by ASP.NET:
Scenario 1: URL does not match a route in the route table.
Generated by ASP.NET MVC:
Scenario 2: URL matches a route, but specifies a controller that doesn't exist.
Scenario 3: URL matches a route, but specifies an action that doesn't exist.
Manually generated:
Scenari...
How to set breakpoints on future shared libraries with a command flag
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With no symbols.
objdump -t /lib/libacl.so
SYMBOL TABLE:
no symbols
objdump -T /lib/libacl.so
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00002bd0 g DF .text 000000d0 ACL_1.0 acl_delete_entry
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(gdb) break 0x0002bd0
(gdb) x/20i acl_delete_entry
0x2bd0 <acl_delete_entry>: stwu r1,-32(r1...
UnboundLocalError on local variable when reassigned after first use
...nitialized. In a fully compiled language, it would just go into the symbol table and wait for the parse, but since it WON'T have the luxury of a second pass, the lexer does a little extra work to make life easier later on. Only, then it sees the OPERATOR, sees that the rules say "if you have an op...