for (int i = 0; i < 10; i++)
{
Blink();     //Appear is my "own language"
}

Blink() here would here would invoke this code:

.hidden {
display: none;
}
.show {    display: inline;
}
<!-- In your HTML -->
<button id="button" class="hidden">test</button>

// In your js
function toggleButton() {
document.getElementById("button").className = 'show';
}