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How to construct a std::string from a std::vector?
...only after assert(not v.empty());, since if the vector is empty, both v[0] and v.front() would invoke undefined behavior. That, aside from the syntactic simplicity of not having to use the address-of operator, is the real benefit of C++11's data() function, which works even on an empty vector.
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How to throw std::exceptions with variable messages?
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what's the difference between this and an std::stringstream? It appears to contain a stringstream, but has (as far as I can tell), no extra functionality.
– matts1
Sep 4 '16 at 1:43
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Add st, nd, rd and th (ordinal) suffix to a number
... use -th (e.g. 11th, pronounced eleventh, 112th,
pronounced one hundred [and] twelfth)
th is used for all other numbers (e.g. 9th, pronounced ninth).
The following JavaScript code (rewritten in Jun '14) accomplishes this:
function ordinal_suffix_of(i) {
var j = i % 10,
k = i % ...
The cast to value type 'Int32' failed because the materialized value is null
...ky abstraction" that yields unexpected behaviour.
One such case is null handling, where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more gene...
No Exception while type casting with a null in java
...ally print methods call String.valueOf(object) method on the input object. And in valueOf method, this check helps to avoid null pointer exception:
return (obj == null) ? "null" : obj.toString();
For rest of your confusion, calling any method on a null object should throw a null pointer exception...
How to find the Number of CPU Cores via .NET/C#?
...er-threading-enabled processors, there are 2 physical processors, 4 cores, and 8 logical processors.
The number of logical processors is available through the Environment class, but the other information is only available through WMI (and you may have to install some hotfixes or service packs to ge...
How can I get list of values from dict?
... or, alternatively [d[k] for k in d] which works for both python2.x and 3.x (Please be advised, I'm not actually suggesting that you use this). Usually you don't actually need a list of values so d.values() is just fine.
– mgilson
Apr 26 '13 at 3:45
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In Android EditText, how to force writing uppercase?
In my Android application I have different EditText where the user can enter information. But I need to force user to write in uppercase letters.
Do you know a function to do that?
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String concatenation in Ruby
...trings you often can gain performance by appending the strings to an array and then at the end put the string together atomically. Then << could be useful?
– PEZ
Dec 18 '08 at 13:12
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What is the difference between single-quoted and double-quoted strings in PHP?
...le confused why I see some code in PHP with string placed in single quotes and sometimes in double quotes.
12 Answers
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