Francisco Tolmasky (2015-01-23T01:03:19.000Z)
tolmasky at gmail.com (2015-01-23T01:26:20.706Z)
Apologies as I believe this has been discussed before ( https://esdiscuss.org/topic/block-scope-direct-non-strict-eval ), but just trying to get some clarification as to the current state of things, and have not been able to find this information (in a format I can understand). Namely, I’m curious whether eval(“let x = 5”) adds x to the current scope, if not in strict mode, at the “top level” (i.e. not in a function) and called directly. My impression was that with let it should not be adding anything to the current scope, but my tests in Mozilla Firefox (in the console) seem to suggest they do: ```javascript > eval(“let x = 5”) > undefined > x > 5 ``` In fact, even in functions: ```javascript > (function() { eval("let xyz = 555"); console.log(xyz) })() > 555 ``` In if statements, it seems to be tacked onto the global scope: ```javascript > if (true) { eval(“let x = 5”) } x > 5 ``` If these are just bugs that’s fine, but if not, could someone tell me the expected behavior? Is it always supposed to act as if its creating a new scope for the blocks, or always *except* for top level evals? Or never? Thanks, Francisco
tolmasky at gmail.com (2015-01-23T01:25:57.014Z)
Apologies as I believe this has been discussed before ( https://esdiscuss.org/topic/block-scope-direct-non-strict-eval ), but just trying to get some clarification as to the current state of things, and have not been able to find this information (in a format I can understand). Namely, I’m curious whether eval(“let x = 5”) adds x to the current scope, if not in strict mode, at the “top level” (i.e. not in a function) and called directly. My impression was that with let it should not be adding anything to the current scope, but my tests in Mozilla Firefox (in the console) seem to suggest they do: ```javascript > eval(“let x = 5”) > undefined > x > 5 ``` In fact, even in functions: > (function() { eval("let xyz = 555"); console.log(xyz) })() > 555 In if statements, it seems to be tacked onto the global scope: > if (true) { eval(“let x = 5”) } x > 5 If these are just bugs that’s fine, but if not, could someone tell me the expected behavior? Is it always supposed to act as if its creating a new scope for the blocks, or always *except* for top level evals? Or never? Thanks, Francisco