{"id":95,"date":"2009-06-15T13:21:25","date_gmt":"2009-06-15T12:21:25","guid":{"rendered":"http:\/\/blogs.igalia.com\/eocanha\/?p=95"},"modified":"2015-11-08T00:21:01","modified_gmt":"2015-11-07T23:21:01","slug":"curiosities-about-parameters-and-variable-declarations-in-javascript","status":"publish","type":"post","link":"https:\/\/eocanha.org\/blog\/2009\/06\/15\/curiosities-about-parameters-and-variable-declarations-in-javascript\/","title":{"rendered":"Curiosities about parameters and variable declarations in Javascript"},"content":{"rendered":"
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    \n
  1. \n
    <html><\/span><\/span><\/div>\n<\/li>\n
  2. \n
    <body><\/span><\/span><\/div>\n<\/li>\n
  3. \n
     <\/div>\n<\/li>\n
  4. \n
    <script<\/span> type<\/span>="application\/javascript;version=1.7"<\/span>><\/span><\/span><\/div>\n<\/li>\n
  5. \n
     <\/div>\n<\/li>\n
  6. \n
    function f1(parameter) {<\/div>\n<\/li>\n
  7. \n
     alert(parameter);<\/div>\n<\/li>\n
  8. \n
    }<\/div>\n<\/li>\n
  9. \n
     <\/div>\n<\/li>\n
  10. \n
    function f2(parameter) {<\/div>\n<\/li>\n
  11. \n
     alert(parameter);<\/div>\n<\/li>\n
  12. \n
     let parameter = "value";<\/div>\n<\/li>\n
  13. \n
    }<\/div>\n<\/li>\n
  14. \n
     <\/div>\n<\/li>\n
  15. \n
    f1("hello");<\/div>\n<\/li>\n
  16. \n
    f2("hello");<\/div>\n<\/li>\n
  17. \n
     <\/div>\n<\/li>\n
  18. \n
    <\/script><\/span><\/span><\/div>\n<\/li>\n
  19. \n
     <\/div>\n<\/li>\n
  20. \n
    <\/body><\/span><\/span><\/div>\n<\/li>\n
  21. \n
    <\/html><\/span><\/span><\/div>\n<\/li>\n<\/ol>\n<\/div>\n<\/div>\n

    Continuing with the “Curiosities” serie, today I bring another one: Javascript doesn’t take too well the definition of a variable with the same name as a function parameter. If you do this, the parameter is lost.<\/p>\n

    Copy the code<\/a> to a local file and try it yourself… Surprisingly, the second alert will print “undefined”.<\/p>\n","protected":false},"excerpt":{"rendered":"

    <html> <body>   <script type="application\/javascript;version=1.7">   function f1(parameter) {  alert(parameter); }   function f2(parameter) {  alert(parameter);  let parameter = "value"; }   f1("hello"); f2("hello");   <\/script>   <\/body> <\/html> Continuing with the “Curiosities” serie, today I bring another one: Javascript doesn’t take too well the definition of a variable with the same name as a … Continue reading Curiosities about parameters and variable declarations in Javascript<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[2],"tags":[],"_links":{"self":[{"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/posts\/95"}],"collection":[{"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/comments?post=95"}],"version-history":[{"count":1,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/posts\/95\/revisions"}],"predecessor-version":[{"id":414,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/posts\/95\/revisions\/414"}],"wp:attachment":[{"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/media?parent=95"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/categories?post=95"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/eocanha.org\/blog\/wp-json\/wp\/v2\/tags?post=95"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}