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![Sam Muir](https://uploads.teamtreehouse.com/production/profile-photos/519432/micro_389132-cactuar_beams.jpg)
Sam Muir
16,745 PointsWhen declaring let, a console error is thrown (Uncaught SyntaxError: Block-scoped declarations)
When I try and open person.html and use let, a console error is thrown (details below):
Navigated to http://port-80-qe2ysckz1w.treehouse-app.com/person.html person.html:14 Uncaught SyntaxError: Block-scoped declarations (let, const, function, class) not yet supported outside strict mode
Don't know too much about Strict Mode, so if anyone can enlighten me then that would be appreciated :)
1 Answer
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,274 Points
Try enabling strict mode for your program.
To enable strict mode, just place this line at the top of your JavaScript code:
"use strict";
![Sam Muir](https://uploads.teamtreehouse.com/production/profile-photos/519432/micro_389132-cactuar_beams.jpg)
Sam Muir
16,745 PointsThanks :)
Steven Parker
230,274 PointsSteven Parker
230,274 Points