https://homeostasis.scs.carleton.ca/wiki/index.php?action=history&feed=atom&title=Mobile_App_Development_2021W_Lecture_6 2026-04-06T04:00:40Z Revision history for this page on the wiki MediaWiki 1.42.1 https://homeostasis.scs.carleton.ca/wiki/index.php?title=Mobile_App_Development_2021W_Lecture_6&diff=22882&oldid=prev 2021-01-27T19:49:16Z

<p><span dir="auto"><span class="autocomment">Video</span></span></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 19:49, 27 January 2021</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Video==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Video==</div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">The video from the lecture given on January 27, 2021 [https://homeostasis.scs.carleton.ca/~soma/mad-2021w/lectures/comp1601-2021w-lec06-20210127.m4v is now available].</ins></div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Notes==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Notes==</div></td></tr> </table>

Soma https://homeostasis.scs.carleton.ca/wiki/index.php?title=Mobile_App_Development_2021W_Lecture_6&diff=22881&oldid=prev 2021-01-27T18:06:36Z

<p>Created page with &quot;==Video== ==Notes== &lt;pre&gt; Lecture 6 ------------ Domain specific languages (DSL) - versus general purpose languages - language designed to specify solutions in a specific...&quot;</p> <p><b>New page</b></p><div>==Video==<br /> <br /> ==Notes==<br /> <br /> &lt;pre&gt;<br /> Lecture 6<br /> ------------<br /> <br /> Domain specific languages (DSL)<br /> - versus general purpose languages<br /> - language designed to specify solutions in a specific domain<br /> - SwiftUI can be thought of as a DSL<br /> - syntax and semantics are specific to SwiftUI, sometimes in non-obvious ways<br /> - but swiftUI is implemented in Swift<br /> - so must follow Swift syntax as well<br /> <br /> DSLs are everywhere in CS, but nowadays we tend to do APIs instead<br /> <br /> APIs are used to express solutions to a specific problem<br /> - but they don&#039;t introduce new syntax, just semantics<br /> <br /> API = application programming interface<br /> - essentially, any library defines an API<br /> <br /> forEach<br /> - used to loop, like for<br /> - but you normally specify an array and a function<br /> - the function is then run on each element of the array in turn<br /> - so it is close to map operation<br /> - but maps return an array of return values<br /> - forEach has no return value<br /> - you don&#039;t explicitly specify the number of iterations<br /> - but it is implicitly defined by the size of the array passed in<br /> - nice because you don&#039;t have to think about figuring out the size of the array<br /> <br /> <br /> Objective C<br /> - we&#039;re not covering Obj-C in class<br /> - but it is important to know about when doing iOS development<br /> <br /> Swift was designed to be a modern language, but had to interoperate with Obj-C<br /> <br /> So, what was Obj-C missing?<br /> - safety<br /> <br /> C isn&#039;t safe<br /> - unrestricted memory access<br /> - C programs segfault (crash)<br /> <br /> Obj-C isn&#039;t safe<br /> - only runtime verification of messages<br /> <br /> Objective C is C plus runtime messages (specified with [ ] syntax)<br /> - directly inspired by Smalltalk<br /> - smalltalk, everything is an object, and objects communicate through messages<br /> - &quot;purest&quot; of the object-oriented languages<br /> <br /> The lack of safety in Obj-C makes it very flexible, but can create problems for less experienced programmers and can cause problems at scale<br /> <br /> Modern languages try to catch as many problems at compile time as possible<br /> - hence, optional types<br /> &lt;/pre&gt;</div>

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