function isPartOfDirectivePrologue(node){var block=node.parent.parent;if(block.type!=="Program"&&(block.type!=="BlockStatement"||!astUtils.isFunction(block.parent))){return false;}// Check the node is at a prologue.
for(var i=0;i<block.body.length;++i){var statement=block.body[i];if(statement===node.parent){return true;}if(!isDirective(statement)){break;}}return false;}
Checks whether or not a given node is a part of directive prologues.
See also: http://www.ecma-international.org/ecma-262/6.0/#sec-directive-prologues-and-the-use-strict-directive
@param {ASTNode} node - A node to check.
@returns {boolean} Whether or not the node is a part of directive prologues.
@private