language agnostic - Does a for loop create two scopes? -

-



imagine following statement (from imaginary c-like language) gets desugared more simple form:

1| (int = 0; < 10; ++i) 2| { 3|     // work 4| }

of course, sticking point int = 0 in initializer, beacuse suppose:

  1. after loop done, i out of scope , can't reference it.
  2. upon reaching line 2, new scope pushed on stack , popped on line 4.

this mean specific for-loop desugar to:

{     int = 0;     while (i < 10)     {         // work         ++i;     } }

leading creation of scope sole purpose of containing incrementer variable.

i understand specifics implementation defined language permits declarations inside classic-style loops. i'm curious if how work under covers, @ least when creating initial ast.

i think thats compiler your. can see if try compile both codes on llvm e.g. clang -s -emit-llvm , compare results.





wiki

Comments

Post a Comment

Popular posts from this blog

elasticsearch - what is the equivalent data type for geo_point in hibernate search? -

-
i using elastic search hibernate search.i want make 1 property data type geo_point ,so can draw tile map using kibana.is there equivalent data type in hibernate search geo_point in elastic search? you can use spatial feature of hibernate search: import org.hibernate.search.annotations.*; @entity @indexed @spatial public class hotel { @latitude double latitude @longitude double longitude // ... } you end geo_point field named location in document. for more information: https://docs.jboss.org/hibernate/stable/search/reference/en-us/html_single/#spatial wiki
Read more

firebase - How to wait value in Ionic 2 -

-
i'm trying wait value may change after execute "this.bookmarlist.take(1).subscribe(..." my problem when run application, execute second if statement "if(found==false)" before execute subscribe. this code may found thing wrong or need add additions solve problem. let loader = this.loadingctrl.create({ content: "", }); let found=false; loader.present().then(()=>{ this.bookmarklist.take(1).subscribe(data=>{ data.foreach(b=>{ if(b.nid==this.appservice.id && b.url==url){ let alert = this.alertctrl.create({ title: 'already bookmarked', subtitle: 'this note image bookmarked', buttons: ['ok'] }); alert.present(); found=true; } }) }) }).then(()=>{ if(found==false){ this.afd.list('/bookmark/').push({ uemail: th...
Read more

Jenkins: find build number for git commit -

-
each commit git repo triggers build of jenkins pipeline. i want retrieve buildnumber of old build commit hash. how can that? i know information exists because can find in ui. some background why want this: when tags commit want create release (by tagging docker image). each build push image containing build number. want find out build number corresponds commit can find image want release. if understand question correctly, first need create git hook trigger new build. part covered in answer how react new tags in git hooks? ', though if using github, bitbucket or gitlab, there may other ways of going it. then when build initiated, there build number provided variable ' build_number ' ,in jenkins. if want include git tag name, can use in script, there seems fews ways: git parameter plugin git tag message plugin typically these plugins create environment variable can consumed scripts. not providing more concrete examples, since not aware of exact ...
Read more