2.4.3 for

Name

for

Description

The for statement lets you repeat a statement or compound statement a specified number of times. The body of a for statement is executed zero or more times until an optional condition becomes false.

Remark

Examples

EX1

void for_ex()
{
	for(int ii = 0; ii < 3; ii++)
	{
		out_int("ii=", ii);
	}
}

for support iterating over range

EX2

//for ([int k, string v] : map) {}
//for (auto& [k, v] : map) {}
void for_map_ex()
{
	omap<int, string> m1;
	m1.Set(100, "Hello");
	m1.Set(200, "World");
	m1.Set(300, "test");
	for ([int k, string v] : m1)
	{
		printf("%d == %s\r\n", k, v);
	}
	for (auto& [key, val], index: m1)
	{
		printf("[%d] %d -> %s\r\n", index, key, val);
	}
}

EX3

//for (double vv : vec) {}
void for_vec()
{
	vector vData = {0.37, 12.049, 856};
	for (double vv : vData) 
	{
		out_double("value=",vv);
	}
}

EX4

//for (auto& ref, size_t idx : vv) {}
//for (auto nn, index : arr) {}
void for_vec2()
{
	vector<string> vData = {"AUD", "YUAN", "HKD"};
	
	for (auto nn, index : vData) 
	{
		printf("%d = %s\n", index, nn);	
		nn = "--"; // value in vData is not changed
	}
	
	for (auto& ref, size_t idx : vData) 
	{
		printf("%d = %s\n", idx, ref);
		ref = "--"; // value in vData is changed
	}
}

Header to Include

See Also

ffor

Reference