Editing Conditional loop (section)

==Types==
The following types are written in [[C++]], but apply to multiple languages.

===While loop===
Checks condition for truthfulness before executing any of the code in the loop.<ref>{{Cite web |title=while loop - cppreference.com |url=https://en.cppreference.com/w/cpp/language/while |access-date=2023-11-07 |website=en.cppreference.com}}</ref> If condition is initially false, the code inside the loop will never be executed. In [[PL/I]] this is a <code>DO WHILE...</code> statement.

<syntaxhighlight lang="c++">
while (condition) {
    // code
}
</syntaxhighlight>

===Do-While loop===
Checks condition for truthfulness after executing the code in the loop. Therefore, the code inside the loop will always be executed at least once. PL/I implements this as a <code>DO UNTIL...</code> statement.

<syntaxhighlight lang="c++">
do {
    // code
} while (condition);
</syntaxhighlight>

===For loop===
A simplified way to create a while loop.<ref>{{Cite web |title=for loop - cppreference.com |url=https://en.cppreference.com/w/cpp/language/for |access-date=2023-11-07 |website=en.cppreference.com}}</ref>

<syntaxhighlight lang="c++">
for (initialization; condition; statement) {
    // code
}
</syntaxhighlight>

'''Initialization''' is executed just once before the loop. '''Condition''' evaluates the boolean expression of the loop. '''Statement''' is executed at the end of every loop.

So for example, the following while loop:

<syntaxhighlight lang="c++">
int i = 0;

while (i < 10) {
    // code
    
    i += 1;
}
</syntaxhighlight>

Could be written as the following for loop:

<syntaxhighlight lang="c++">
for (int i = 0; i < 10; ++i) {
    // code
}
</syntaxhighlight>

===For-Each loop===
A for-each loop is essentially equivalent to an [[iterator]]. It allows a program to iterate through a data structure without having to keep track of an index. It is especially useful in Sets which do not have indices. An example is as follows:

<syntaxhighlight lang="c++">
std::vector<std::string> range = { "apple", "banana", "orange" };

for (auto item: range) {
    // code
}
</syntaxhighlight>