<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Feb 2, 2016, at 11:14 AM, Matthew Johnson <<a href="mailto:matthew@anandabits.com" class="">matthew@anandabits.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">I know there is concern about overloading the semantics of `_` which is unfortunate as IMO it is the best symbol to serve as a placeholder. I wonder if there has been confusion about the semantics<span class="Apple-converted-space"> </span></span><b class="" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">in practice</b><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class=""> in languages like Scala where it is used in both ways. Is there any evidence that this has been a problem?</span></div></blockquote></div><br class=""><div class="">Not a super scientific study, but if you google "scala underscore", several of the results on the first page indicate confusion or bewilderment:</div><div class=""><br class=""></div><div class=""><h3 class="r" style="font-size: 18px; font-weight: normal; margin: 0px; padding: 0px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: rgb(34, 34, 34); font-family: arial, sans-serif;"><a href="https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwj-08ju59nKAhWj26YKHRuVBh8QFggdMAA&url=http%3A%2F%2Fananthakumaran.in%2F2010%2F03%2F29%2Fscala-underscore-magic.html&usg=AFQjCNEbIIoppVNYAjr6wqxL4byR9I1fAw&sig2=Hlw6hEFfsPqvlDvEFaDoyQ" style="color: rgb(102, 0, 153); cursor: pointer; text-decoration: none;" class="">Scala _ [underscore] magic ยท Anantha Kumaran</a></h3><div class=""><br class=""></div></div><div class=""><h3 class="r" style="font-size: 18px; font-weight: normal; margin: 0px; padding: 0px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: rgb(34, 34, 34); font-family: arial, sans-serif;"><a href="https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwj-08ju59nKAhWj26YKHRuVBh8QFggjMAE&url=http%3A%2F%2Fstackoverflow.com%2Fquestions%2F8000903%2Fwhat-are-all-the-uses-of-an-underscore-in-scala&usg=AFQjCNHVNCJVosr0IzZYmh8pJRdnXTnf6g&sig2=vqWgzaddf2kEkWrdgFQuoQ&bvm=bv.113034660,d.dGY" style="color: rgb(102, 0, 153); cursor: pointer; text-decoration: none;" class="">What are all the uses of an underscore in Scala? - Stack ...</a></h3><div class=""><br class=""></div><h3 class="r" style="font-size: 18px; font-weight: normal; margin: 0px; padding: 0px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: rgb(34, 34, 34); font-family: arial, sans-serif;"><a href="https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0ahUKEwj-08ju59nKAhWj26YKHRuVBh8QFggqMAI&url=http%3A%2F%2Fwww.slideshare.net%2Fnormation%2Fscala-dreaded&usg=AFQjCNEs5fGA4e8NsU10--FKfOyga8aEaA&sig2=mlWWAnJgFVxSpA4UtA2wyw" style="color: rgb(102, 0, 153); cursor: pointer; text-decoration: none;" class="">Scala dreaded underscore - SlideShare</a></h3><div class=""><br class=""></div></div><div class=""><h3 class="r" style="font-size: 18px; font-weight: normal; margin: 0px; padding: 0px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: rgb(34, 34, 34); font-family: arial, sans-serif;"><a href="http://www.scala-lang.org/old/node/2916.html" style="color: rgb(102, 0, 153); cursor: pointer; text-decoration: none;" class="">underscore confusion | The Scala Programming Language</a></h3><div class=""><br class=""></div></div><div class="">-Joe</div></body></html>