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comparison demo/prose @ 455:d4a81273d4b1

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Nested demo
author Adam Chlipala <adamc@hcoop.net>
date Tue, 04 Nov 2008 09:33:35 -0500
parents 0ce90d4d9ae7
children ddd363e856ff
comparison
equal deleted inserted replaced
454:9163f8014f9b 455:d4a81273d4b1
51 <p>In the implementation of <tt>Counter.counter</tt>, we see the notation <tt>{[...]}</tt>, which uses type classes to inject values of different types (<tt>int</tt> in this case) into XML. It's probably worth stating explicitly that XML fragments <i>are not strings</i>, so that the type-checker will enforce that our final piece of XML is valid.</p> 51 <p>In the implementation of <tt>Counter.counter</tt>, we see the notation <tt>{[...]}</tt>, which uses type classes to inject values of different types (<tt>int</tt> in this case) into XML. It's probably worth stating explicitly that XML fragments <i>are not strings</i>, so that the type-checker will enforce that our final piece of XML is valid.</p>
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53 form.urp 53 form.urp
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55 <p>Here we see a basic form. The type system tracks which form inputs we include, and it enforces that the form handler function expects a record containing exactly those fields, with exactly the proper types.</p> 55 <p>Here we see a basic form. The type system tracks which form inputs we include, and it enforces that the form handler function expects a record containing exactly those fields, with exactly the proper types.</p>
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57 nested.urp
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59 <p>Here is an implementation of the tiny challenge problem from <a href="http://www.accursoft.co.uk/web/">this web framework comparison</a>. Using nested function definitions, it is easy to persist state across clicks.</p>
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57 listShop.urp 61 listShop.urp
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59 <p>This example shows off algebraic datatypes, parametric polymorphism, and functors.</p> 63 <p>This example shows off algebraic datatypes, parametric polymorphism, and functors.</p>
60 64