cream-and-sugar/dist/compiler/nodes/Import.js

A deliciously functional syntax for JavaScript with native support for JSX

'use strict';

var _utils = require('../utils');

/*
 * Translate imports 1-1.
 */
(0, _utils.compile)(_utils.nodes.ImportNode, function () {
  var _this = this;

  // Native Import
  // const getFrom = this.file ? ` from ${this.file.compile(true)}` : '';
  // const toImport = this.toImport.compile(true);
  // return `import ${toImport}${getFrom}`;

  // Traditional Import
  // Experimenting with this to see if it helps us import
  // modules in separate threads.

  // import 'foo'
  if (!this.file) {
    return 'require(' + this.toImport.toDestructure.compile(true) + ')';
  } else {

    var ref = void 0,
        base = void 0;
    var file = this.file.compile(true);
    switch (this.toImport.destrType) {

      // import foo from 'foo'
      case 'Lookup':
        return 'const ' + this.toImport.toDestructure.compile(true) + ' = require(' + file + ')';

      // import 'foo' from 'foo'
      case 'String':
        return (0, _utils.die)(this, 'Can not use a string as a variable name in an import statement.');

      // import [ foo, bar ] from 'foo'
      // import {{ foo, bar }} from 'foo'
      case 'Array':
      case 'Tuple':
        ref = 'ref' + (this.shared.refs += 1) + '_';
        // Use var here so it can be redeclared in the REPL.
        base = 'var ' + ref + ' = require(' + file + ');\n';
        this.toImport.toDestructure.items.forEach(function (item, index) {
          var varName = item.compile(true);
          base += 'const ' + varName + ' = ' + ref + '[' + index + ']';
          index !== _this.toImport.toDestructure.items.length - 1 && (base += ';\n');
        });
        return base;

      // import { foo, bar } from 'foo'
      case 'Keys':
        ref = 'ref' + (this.shared.refs += 1) + '_';
        // Use var here so it can be redeclared in the REPL.
        base = 'var ' + ref + ' = require(' + file + ');\n';
        this.toImport.toDestructure.forEach(function (item, index) {
          var varName = item.compile(true);
          base += 'const ' + varName + ' = ' + ref + '.' + varName;
          index !== _this.toImport.toDestructure.length - 1 && (base += ';\n');
        });
        return base;

      // import { foo: f, bar: b } from 'foo'
      case 'Object':
        ref = 'ref' + (this.shared.refs += 1) + '_';
        // Use var here so it can be redeclared in the REPL.
        base = 'var ' + ref + ' = require(' + file + ');\n';
        this.toImport.toDestructure.pairs.forEach(function (item, index) {
          var varName = item.right.compile(true);
          var propName = item.left.compile(true);
          base += 'const ' + varName + ' = ' + ref + '.' + propName;
          index !== _this.toImport.toDestructure.pairs.length - 1 && (base += ';\n');
        });
        return base;

      // import [ head | tail ] from 'foo'
      case 'HeadTail':
        ref = 'ref' + (this.shared.refs += 1) + '_';
        // Use var here so it can be redeclared in the REPL.
        base = 'var ' + ref + ' = require(' + file + ');\n';
        this.toImport.toDestructure.forEach(function (item, index) {
          var varName = item.compile(true);
          if (index === 0) {
            base += 'const ' + varName + ' = ' + ref + '[0]';
          } else {
            base += 'const ' + varName + ' = ' + ref + '.slice(1)';
          }
          index !== _this.toImport.toDestructure.length - 1 && (base += ';\n');
        });
        return base;

      // import [ lead || last ] from 'foo'
      case 'LeadLast':
        ref = 'ref' + (this.shared.refs += 1) + '_';
        // Use var here so it can be redeclared in the REPL.
        base = 'var ' + ref + ' = require(' + file + ');\n';
        this.toImport.toDestructure.forEach(function (item, index) {
          var varName = item.compile(true);
          if (index === 0) {
            base += 'const ' + varName + ' = ' + ref + '.slice(0, ' + ref + '.length - 1)';
          } else {
            base += 'const ' + varName + ' = ' + ref + '[' + ref + '.length - 1]';
          }
          index !== _this.toImport.toDestructure.length - 1 && (base += ';\n');
        });
        return base;

      default:
        (0, _utils.die)(this, 'Can not import a ' + this.toImport.type + '.');
    }
  }
});