{"id":5363,"date":"2014-03-30T21:07:10","date_gmt":"2014-03-30T21:07:10","guid":{"rendered":"https:\/\/unknownerror.org\/index.php\/2014\/03\/30\/does-python-2-5-have-an-equivalent-to-tcls-uplevel-command-collection-of-common-programming-errors\/"},"modified":"2014-03-30T21:07:10","modified_gmt":"2014-03-30T21:07:10","slug":"does-python-2-5-have-an-equivalent-to-tcls-uplevel-command-collection-of-common-programming-errors","status":"publish","type":"post","link":"https:\/\/unknownerror.org\/index.php\/2014\/03\/30\/does-python-2-5-have-an-equivalent-to-tcls-uplevel-command-collection-of-common-programming-errors\/","title":{"rendered":"does python 2.5 have an equivalent to Tcl's uplevel command?-Collection of common programming errors"},"content":{"rendered":"

In general, what you ask is not possible (with the results you no doubt expect). E.g., imagine the “any code” is x = 23<\/code>. Will this add a new variable x<\/code> to your caller’s set of local variables, assuming you do find a black-magical way to execute this code “in the caller”? No it won’t — the<\/strong> crucial optimization performed by the Python compiler is to define once and for all, when def<\/code> executes, the exact set of local variables (all the barenames that get assigned, or otherwise bound, in the function’s body), and turn every access and setting to those barenames into very fast indexing into the stackframe. (You could<\/em> systematically defeat that crucial optimization e.g. by having an exec ''<\/code> at the start of every possible caller — and see your system’s performance crash through the floor in consequence).<\/p>\n

Except<\/em> for assigning to the caller’s local barenames, exec thecode in thelocals, theglobals<\/code> may do roughly what you want, and the inspect<\/code> module lets you get the locals and globals of the caller in a semi-reasonable way (in as far as deep black magic — which would make me go postal on any coworker suggesting it be perpetrated in production code — can ever be honored with the undeserved praise of calling it “semi-reasonable”, that is;-).<\/p>\n

But you do specify “I want to be able to execute any code.” and the only solution to that<\/em> unambiguous specification (and thanks for being so precise, as it makes answering easier!) is: then, use a different programming language.<\/p>\n","protected":false},"excerpt":{"rendered":"

In general, what you ask is not possible (with the results you no doubt expect). E.g., imagine the “any code” is x = 23. Will this add a new variable x to your caller’s set of local variables, assuming you do find a black-magical way to execute this code “in the caller”? No it won’t […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-5363","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/5363","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/comments?post=5363"}],"version-history":[{"count":0,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/5363\/revisions"}],"wp:attachment":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/media?parent=5363"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/categories?post=5363"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/tags?post=5363"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}