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#include <string>
#include <vector>
#include <mutex>
#include <cstdlib>
#include <ctime>
#include <cstdio>
fill: (
out x: std::string,
in value: std::string,
in count: int
)
pre( value.size() >= count, "fill: value must contain at least count elements" )
= {
x = value.substr(0, count);
}
main: () -> int =
{
x: std::string; // note: uninitialized!
if flip_a_coin() {
x = "xyzzy";
}
else {
// fill( out x, "plugh", 40 ); // note: constructs x!
}
print_decorated(x);
}
// Print! A one-expression function body...
//
print_decorated: (x:_) = std::cout << ">> [" << x << "]\n";
// Flip a coin! Exercise <mutex> <cstdlib> <ctime> and 'as'...
//
rand_init_flag: std::once_flag = ();
flip_a_coin: () -> bool = {
std::call_once(rand_init_flag, srand, time(nullptr) as unsigned );
return std::rand()%2;
}
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