有条件地要求使用javascript模块

Question

I'm entering the conditional as expected (as proven by a console that is only hit in the if statement if process.env.BROWSER === true , but the require inside the if statement is still getting hit nomatter if process.env.BROWSER === true or process.env.BROWSER === false and this is causing and error when process.env.BROWSER === false . If I comment out the first require, then when process.env.BROWSER === false there is no error.

I suspect that all requires are somehow called when JS is compiling, but if that's the case how can I conditionally require a module? What's exactly happening here?

if (process.env.BROWSER) {
    language['ES'].push(require('promise?global,locale-es-ES!react-intl/locale-data/es'));
} else{
    language['ES'].push(function () {
      return Promise.resolve(require('react-intl/locale-data/es'));
    });
}

using module.require like this works in react-native but throws a TypeError: module.require is not a function when in the Browser

if (process.env.BROWSER) {
    language['ES'].push(module.require('promise?global,locale-es-ES!react-intl/locale-data/es'));
} else{
    language['ES'].push(function () {
      return Promise.resolve(require('react-intl/locale-data/es'));
    });
}

trying to find a reference to module like this gives the TypeError: Cannot read property 'require' of undefined

if (process.env.BROWSER) {
        language['ES'].push(require('react-intl').module.require('promise?global,locale-es-ES!react-intl/locale-data/es'));
    } else{
        language['ES'].push(function () {
          return Promise.resolve(require('react-intl/locale-data/es'));
        });
    }

Answer 1

I had faced same problem as above but with nodejs and react native.

I overcame the problem by using module.require() for nodejs module. Try if you can do this in your case(Or any way to avoid a direct require for browser case).

React native would not allow conditional require, and I think does a static analysis loading all require before.