<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; 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-webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div><span class="Apple-style-span" style="font-size: medium;"><font class="Apple-style-span" color="#0000FF" face="'Gill Sans'">That's very nice! I like it. I think we can use it....</font></span></div></span></span></span></span></span></span></span></span></div></span></span></div><div><br class="webkit-block-placeholder"></div><div>Right now I am tracking bugs in range checking. Some were introduced by my LONGINT changes (sigh!) but others appear to have been around a while before that.</div><div><br></div><div>For example:</div><div><br></div><div>VAR s: CARDINAL := LAST(INTEGER);</div><div>BEGIN INC(s) END;</div><div><br></div><div>did not result in a run-time error. I think I have fixed that now (commit to come).</div><div><br></div><div>But, even worse:</div><div><br></div><div>VAR s: CARDINAL := LAST(INTEGER);</div><div><div>BEGIN WITH x = s DO x := VAL(ORD(x) + 1, CARDINAL) END END;</div><div><br></div><div>also does not give a run-time error.</div><div><br></div><div>The result is that you can store FIRST(INTEGER) in a CARDINAL. Yikes!</div><div><br></div></div><div><div>On 9 Jan 2010, at 21:54, Rodney M. Bates wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>When writing my original proposal, I agonized at length over whether<br>to allow (subranges of) LONGINT to be the index type of an array type. In the<br>end, I decided that gave a poor ratio of practical benefit to language<br>and implementation complexity.<br><br>However, note, from 2.6.3, "Designators,<br><br>"a[i]<br> denotes the (i + 1 - FIRST(a))-th element of the array a. The expression a[i] is a<br> designator if a is, and is writable if a is. The expression i must be assignable<br>--------------------------------------------------------------------------^<br> to the index type of a. The type of a[i] is the element type of a."<br><br>So, by existing rules about assignability, when referring to an element of an<br>array, the subscript expression could have base type LONGINT, and would just<br>be "assigned" in the usual way to the index type, a subrange of INTEGER.<br>This is one of the dozen or so places assignability is used in the language.<br><br><br><br>Jay K wrote:<br><blockquote type="cite">Index array by longint?<br></blockquote><blockquote type="cite">With runtime check that it is <= LAST(INTEGER)?<br></blockquote><blockquote type="cite"> Or really, with runtime bounds check against the array size.<br></blockquote><blockquote type="cite"> Seems reasonable?<br></blockquote><blockquote type="cite">Aids the rd/wr change.<br></blockquote><blockquote type="cite">A little bit of pain to implement..unless INTEGER and LONGINT have a common base...<br></blockquote><blockquote type="cite"> - Jay<br></blockquote></div></blockquote></div><br></body></html>