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Bash arithmetic expression's side effects not executed

bash,post-increment,arithmetic-expressions,side-effects
$ declare -i i=0 $ for j in {0..2}; do echo "${j} $((i++))"; done 0 0 1 1 2 2 $ for j in {0..2}; do echo "$(echo "${j} $((i++))")"; done 0 3 1 3 2 3 $ Why i doesn't get incremented in the 2nd for loop? (Yes, I...

What are the historical reasons C languages have pre-increments and post-increments?

c++,c,post-increment,decrement,pre-increment
(Note: I am not asking about the definitions of pre-increment vs. post-increment, or how they are used in C/C++. Therefore, I do not think this is a duplicate question.) Developers of C (Dennis Ritchie et al) created increment and decrement operators for very good reasons. What I don't understand is...

Why is “ref” not assigning updated value to the next field?

c#,.net,pass-by-reference,ref,post-increment
I've found a really cool feature of a compilator. However, I cannot understand logic of this behaviour. static int IncrementValue(ref int i) { return i++;} and Main method: static void Main(string[] args) { int a = 2; int b = IncrementValue(ref a); Console.WriteLine(a+b); } The output is 5. My question...

Is post-increment operator guaranteed to run instantly?

c,c89,post-increment,ansi-c
Let's say I have the following code: int i = 0; func(i++, i++); The increment is happening right after returning the value? Is it guaranteed that the first argument will be 0, and the second argument will be 1?...

i++ vs. ++i in a JavaScript for loop

javascript,for-loop,post-increment,pre-increment
Because of JSLint, I almost always use i += 1 to increment a JavaScript for loop, but for quick and dirty scripts, I use i++ instead. However, I see a lot of for loops in other people's code in which they increment i by doing ++i instead. As far as...

Difference between pre and post decrement in recursive function argument

c++,recursion,post-increment,pre-increment
I have following sample code where i used pre-decrement void function(int c) { if(c == 0) { return; } else { cout << "DP" << c << endl; function(--c); cout << c << endl; return; } } This function give output for input 4 as : DP3 DP2 DP1 DP0...

post and pre increment in for loop. string length without library function in C

c,post-increment,pre-increment
I am trying to find Length of a string w/o using library function. char card[16]; //card number in char array. unsigned int cardno[16]={0}; //card number in int array for calculations. int i,length=0,len; printf("Credit Card Number[without any spaces]: "); gets(card); for(i=0;card[i]!='\0';i++); len=i; length=strlen(card); printf("%d %d",len,length); But if i enter a 16...

post and pre increment not working as expected for REPL variable in scala

java,scala,compiler-errors,integer,post-increment
I know that there is no ++ and -- in scala instead I have to use += and -= But when I try scala> var a=2 a: Int = 2 scala> a +=1 scala> a res11: Int = 3 the above works fine but not the below one scala> 5...