ktyr report

value is stringを指定しないと正しく動作しない

function isString(value:unknown):value is string{
    return typeof value === "string";
}
function showData(value:number|string){
    if(isString(value)){
        console.log(value.toUpperCase());
    }else{
        console.log(value.toFixed(2));
    }
}