reactjs - Which is better performance: to import once and pass as props to <Row/> or import within each <Row/> component? -


i guess general question be, require more handling pass something props <child something={something}/> or import something within <child/>.

so example, have: 

import { basestyle } '../styles/common.js';  <flatlist   data={this.state.datasource}   renderitem={this.renderitem} />  renderitem() {   return (     <customrow       basestyle={basestyle}     />   ) }

or better import basestyle within <customrow/> component?

i assume @ least <list/> component, react/rn smart enough cache imports <row/> components until has finished rendering every <row/>.

does have theories this?

so quite simple test out. did set variable

var time = date.now();

outside of class above import statements , console logged time in componentdidmount(). showed same time registered first date.now() assignment var time, every time component re-rendered. think it's safe assume behavior if it's possible import constant, instead of passing down props components recheck due potential updates.


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