Vlad Feninets

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}

appendYaMetrix() {
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	yaScript.innerHTML = `(function(w, d, n, s, t) {
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                async: true
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        t = d.getElementsByTagName("script")[0];
        s = d.createElement("script");
        s.type = "text/javascript";
        s.src = "//an.yandex.ru/system/context.js";
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    document.head.appendChild(yaScript)
}

componentDidMount() {
	this.appendYaMetrix()
}

gulp.watch('./src/js/*.js', function() {
        setTimeout(function () {
            gulp.start('js');
        }, 300);
    });

$(document).ready(function() {
     ...
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