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C99 - why are false and true defined as 0 and 1 and not as ((bool)0) and ((bool)1)?

Just stumbled across an assert, that failed, as it compared false to the returntype of a function, as the function itself returned a bool and the assert checked not only the value, but also the type o[详细]

2023-03-19 02:41 分类：问答
Why can't you have multiple interfaces in a bounded wildcard generic?

I know there\'s all sorts of counter-intuitive properties of Java\'s generic types. Here\'s one in particular that I don\'t understand, and which I\'m hoping someone can explain to me. When specifying[详细]

2023-03-19 01:02 分类：问答
Why can't we define a variable inside an if statement?

Maybe this question has been answered before, but the word if occurs so often it\'s hard to find it. The example doesn\'t make sense (the expression is always true), but it illustrates my question.[详细]

2023-03-17 02:32 分类：问答
Arrays as separate type

Some scripting languages, such as Python and Javascript, have arrays (aka lists) as a separate datatype from hash tables (aka dictionaries, maps, objects). In other scripting languages, such as PHP an[详细]

2023-03-16 20:51 分类：问答
What role does string immutability play in the explaination of string references to developers?

In one form or another I encounter the following question often (posed, here, in pseudo-code): String myString = \"Hello\"[详细]

2023-03-16 19:16 分类：问答
Faulty behavior in Java in conditional expression

A simple expression: Object val = true ? 1l : 0.5; What type is val? Well, logically, val should be a Long object with value 1. But Java thinks that val is a Double with value 1.0.[详细]

2023-03-16 08:59 分类：问答
C++ exceptions and signal handlers

I am reading The Design and Evolution of C++, by Bjarne Stroustrup. Regarding exeception handling and asynchronous signals it is mentioned as below:[详细]

2023-03-16 05:48 分类：问答
Why does Python's itertools.permutations contain duplicates? (When the original list has duplicates)

It is universally agreed that a list of n distinct symbols has n! permutations. However, when the symbols are not distinct, the most common convention, in mathematics and elsewhere, seems to be to cou[详细]

2023-03-16 05:30 分类：问答
Why do the valueOf/parse methods on the number classes reject valid numbers in Java 7?

Neither underscores: scala> java.lang.Float.valueOf(\"1_2_3.4_5_6\") java.lang.NumberFormatException: For input string: \"1_2_3.4_5_6\"[详细]

2023-03-15 04:49 分类：问答
When auto is used against array, why it's converted to pointer and not reference?

See the below example: int arr[10]; int *p = arr; // 1st valid choice int (&r)[10] = arr; // 2nd valid choice[详细]

2023-03-14 13:48 分类：问答