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| Generation</a> |
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| One of the most interesting capabilities of <a href="http://cgi.di.uoa.gr/~smaragd/fc++/" target="_top">FC++</a> |
| is the generation of infinite lazy lists which are evaluated only at need. |
| The most simple example of this is |
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| <pre class="programlisting"><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">)</span> |
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| which returns the generator for integers 1,2,3,..... infinity. |
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| <pre class="programlisting"><span class="identifier">take</span><span class="special">(</span><span class="number">4</span><span class="special">,</span><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">))</span> |
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| returns a list of the first 4 of the list. |
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| <pre class="programlisting"><span class="identifier">at</span><span class="special">(</span><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">),</span><span class="number">3</span><span class="special">)</span> |
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| returns the fourth member using zero indexed access. Both of the lists |
| returned are lazy and only evaluated when the list members are accessed. |
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