title: I'm not getting back number in react typescript
body: <p>I have a code like this:</p>
  <pre><code>type State = {
    ...
    PromotionIDs: Number[];
    autoAdjustUsage: AutoAdjustUsage[]
  };
  
  const InitState: State = {
    ...
    PromotionIDs: [],
    autoAdjustUsage: []
  };
  
  
      const contracts = this.state[PointsTableType.ELIGIBLE].contracts;
      let result = this.state.PromotionIDs.map(i=&gt;Number(i));
      const autoAdjustPayload = {
        promotionIDs: result,
        usageYears: contracts.map(x =&gt; ({ usageYearId: x.usageId, applied: x.appliedPoints,usageType:x.usageType }))
      };
  
      console.log(&quot;this.state.PromotionIDs: &quot;, this.state.PromotionIDs)
  </code></pre>
  <p>I'm not getting back any number when I console.log PromotionID. Does anyone know how can I fix this?</p>