How to use the esprima-fb.Syntax.FunctionDeclaration function in esprima-fb

// Always munge identifiers that were declared within the method function
    // scope
    if (utils.identWithinLexicalScope(node.name, state, state.methodFuncNode)) {
      return true;
    }

    // Always munge private keys on object literals defined within a method's
    // scope.
    if (path[0].type === Syntax.Property
        && path[1].type === Syntax.ObjectExpression) {
      return true;
    }

    // Always munge function parameters
    if (path[0].type === Syntax.FunctionExpression
        || path[0].type === Syntax.FunctionDeclaration
        || path[0].type === Syntax.ArrowFunctionExpression) {
      for (var i = 0; i < path[0].params.length; i++) {
        if (path[0].params[i] === node) {
          return true;
        }
      }
    }
  }
  return false;
};

visitFunctionDefinitionArguments.test = function(node, path, state) {
  return (
    node.type === Syntax.FunctionExpression ||
    node.type === Syntax.FunctionDeclaration ||
    node.type === Syntax.MethodDefinition
  ) && (
    node.params && node.params.length > 0 || // function expression/declaration
    node.value && node.value.params.length > 0 // method definition
  );
};

}


    // export DECLARATION
    } else {
      switch (node.declaration.type) {
        // export var name = value
        case Syntax.VariableDeclaration:
          utils.move(node.declaration.range[0], state);
          node.declaration.declarations.forEach(function(declaration) {
            utils.catchup(declaration.id.range[1], state);
            utils.append(' = module.exports.' + declaration.id.name, state);
            traverse(declaration.init, path, state);
          });
          break;
        case Syntax.FunctionDeclaration:
          name = node.declaration.id.name;
          utils.move(node.declaration.range[0], state);
          traverse(node.declaration, path, state);
          utils.append(' module.exports.' + name + ' = ' + name + ';', state);
          break;
        case Syntax.ClassDeclaration:
          name = node.declaration.id.name;
          utils.move(node.declaration.range[0], state);
          traverse(node.declaration, path, state);
          utils.append('module.exports.' + name + ' = ' + name + ';', state);
          break;
        default:
          assert(false, "unknown declaration: " + node.declaration.type);
      }
    }

// Always munge identifiers that were declared within the method function
    // scope
    if (utils.identWithinLexicalScope(node.name, state, state.methodFuncNode)) {
      return true;
    }

    // Always munge private keys on object literals defined within a method's
    // scope.
    if (path[0].type === Syntax.Property
        && path[1].type === Syntax.ObjectExpression) {
      return true;
    }

    // Always munge function parameters
    if (path[0].type === Syntax.FunctionExpression
        || path[0].type === Syntax.FunctionDeclaration
        || path[0].type === Syntax.ArrowFunctionExpression) {
      for (var i = 0; i < path[0].params.length; i++) {
        if (path[0].params[i] === node) {
          return true;
        }
      }
    }
  }
  return false;
};

process(traverse, node.callee.object, path, state);
    utils.append(')', state);
    if (node.callee.property.type === Syntax.Identifier) {
      utils.append('.', state);
      process(traverse, node.callee.property, path, state);
    } else {
      utils.append('[', state);
      process(traverse, node.callee.property, path, state);
      utils.append(']', state);
    }
    utils.append('.apply(' + tempVar, state);
  } else {
    // Input  = max(1, 2, ...list)
    // Output = max.apply(undefined, [1, 2].concat(list))
    var needsToBeWrappedInParenthesis =
      node.callee.type === Syntax.FunctionDeclaration ||
      node.callee.type === Syntax.FunctionExpression;
    if (needsToBeWrappedInParenthesis) {
      utils.append('(', state);
    }
    process(traverse, node.callee, path, state);
    if (needsToBeWrappedInParenthesis) {
      utils.append(')', state);
    }
    utils.append('.apply(undefined', state);
  }
  utils.append(', ', state);

  var args = node.arguments.slice();
  var spread = args.pop();
  if (args.length || node.type === Syntax.NewExpression) {
    utils.append('[', state);

// Always munge identifiers that were declared within the method function
    // scope
    if (utils.identWithinLexicalScope(node.name, state, state.methodFuncNode)) {
      return true;
    }

    // Always munge private keys on object literals defined within a method's
    // scope.
    if (path[0].type === Syntax.Property
        && path[1].type === Syntax.ObjectExpression) {
      return true;
    }

    // Always munge function parameters
    if (path[0].type === Syntax.FunctionExpression
        || path[0].type === Syntax.FunctionDeclaration
        || path[0].type === Syntax.ArrowFunctionExpression) {
      for (var i = 0; i < path[0].params.length; i++) {
        if (path[0].params[i] === node) {
          return true;
        }
      }
    }
  }
  return false;
};

foundMatchingChild = containsChildMatching(child, matcher);
    }
  }
  analyzeAndTraverse(
    nodeTypeAnalyzer,
    nodeTypeTraverser,
    node,
    []
  );
  return foundMatchingChild;
}

var scopeTypes = {};
scopeTypes[Syntax.ArrowFunctionExpression] = true;
scopeTypes[Syntax.FunctionExpression] = true;
scopeTypes[Syntax.FunctionDeclaration] = true;
scopeTypes[Syntax.Program] = true;

function getBoundaryNode(path) {
  for (var ii = 0; ii < path.length; ++ii) {
    if (scopeTypes[path[ii].type]) {
      return path[ii];
    }
  }
  throw new Error(
    'Expected to find a node with one of the following types in path:\n' +
    JSON.stringify(Object.keys(scopeTypes))
  );
}

function getTempVar(tempVarIndex) {
  return '$__' + tempVarIndex;

function _nodeIsFunctionWithRestParam(node) {
  return (node.type === Syntax.FunctionDeclaration
          || node.type === Syntax.FunctionExpression
          || node.type === Syntax.ArrowFunctionExpression)
         && node.rest;
}

if (!foundMatchingChild) {
      foundMatchingChild = containsChildMatching(child, matcher);
    }
  }
  analyzeAndTraverse(
    nodeTypeAnalyzer,
    nodeTypeTraverser,
    node,
    []
  );
  return foundMatchingChild;
}

var scopeTypes = {};
scopeTypes[Syntax.FunctionExpression] = true;
scopeTypes[Syntax.FunctionDeclaration] = true;
scopeTypes[Syntax.Program] = true;

function getBoundaryNode(path) {
  for (var ii = 0; ii < path.length; ++ii) {
    if (scopeTypes[path[ii].type]) {
      return path[ii];
    }
  }
  throw new Error(
    'Expected to find a node with one of the following types in path:\n' +
    JSON.stringify(Object.keys(scopeTypes))
  );
}

function getTempVar(tempVarIndex) {
  return '$__' + tempVarIndex;

function _nodeIsFunctionWithRestParam(node) {
  return (node.type === Syntax.FunctionDeclaration
          || node.type === Syntax.FunctionExpression
          || node.type === Syntax.ArrowFunctionExpression)
         && node.rest;
}