text: const acorn = require("acorn")
  
  function makeConstRTS() {
    const rts = {
      type: 'VariableDeclaration',
      declarations: [
        {
          type: 'VariableDeclarator',
          id: { type: 'Identifier', name: 'RTS' },
          init: {
            type: 'CallExpression',
            callee: { type: 'Identifier', name: 'require' },
            arguments: [
              {
                type: 'Literal',
                value: 'gambit-scheme',
                raw: "'gambit-scheme'"
              }
            ],
            optional: false
          }
        }
      ],
      kind: 'const'
    };
    return rts;
  }
  
  function prependConstRTS(source) {
    const AST = (typeof source === 'string') ?  acorn.parse(content) : source;
    const constRTS = makeConstRTS();
  
    AST.body.unshift(constRTS);
    return AST;
  }
  
  module.exports = prependConstRTS
  