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@page "/Concat"
<PageTitle>Concatenator</PageTitle>
<PageScript Src="./Components/Pages/Concat.razor.js"/>
<main>
<p>A "concatenative language"</p>
<form id="form">
<textarea id="input" placeholder="1 2 +" rows="5"></textarea>
<input type="submit" value="Run program">
</form>
<Log/>
<fieldset class="docs">
<legend>Predefined operations</legend>
<details>
<summary>dup</summary>
<p>Duplicates the top value on the stack</p>
<div class="flex-spread">
<span>[1, 2, 3]</span>
<span>dup</span>
</div>
<div class="flex-spread">
<span>[1, 1, 2, 3]</span>
<span></span>
</div>
</details>
<details>
<summary>drop</summary>
<p>Drops the top value on the stack</p>
<div class="flex-spread">
<span>[1, 2, 3]</span>
<span>drop</span>
</div>
<div class="flex-spread">
<span>[2, 3]</span>
<span></span>
</div>
</details>
<details>
<summary>swap</summary>
<p>Swaps the top two values on the stack</p>
<div class="flex-spread">
<span>[1, 2, 3]</span>
<span>swap</span>
</div>
<div class="flex-spread">
<span>[2, 1, 3]</span>
<span></span>
</div>
</details>
<details>
<summary>skip</summary>
<p>Skips forward in the program by the amount on the top of the stack.
If the value on the top of the stack is 0 or negative,
the value is dropped and the program does not skip ahead.
</p>
<div class="flex-spread">
<span>[1, 2, 3]</span>
<span>skip drop dup</span>
</div>
<div class="flex-spread">
<span>[2, 3]</span>
<span>dup</span>
</div>
<div class="flex-spread">
<span>[2, 2, 3]</span>
<span></span>
</div>
Or
<div class="flex-spread">
<span>[-1, 2, 3]</span>
<span>skip drop dup</span>
</div>
<div class="flex-spread">
<span>[2, 3]</span>
<span>drop dup</span>
</div>
<div class="flex-spread">
<span>[3]</span>
<span>dup</span>
</div>
<div class="flex-spread">
<span>[3, 3]</span>
<span></span>
</div>
</details>
<details>
<summary>: word ... ;</summary>
<p>Creates a new definition.</p>
<p>Example: ": double 2 * ;" defines a new word called double. Any subsequent mention of double will
replace the word with its definition.</p>
<div class="flex-spread">
<span>[]</span>
<span>: double 2 * ; 3 double</span>
</div>
<div class="flex-spread">
<span>[]</span>
<span>3 double</span>
</div>
<div class="flex-spread">
<span>[3]</span>
<span>double</span>
</div>
<div class="flex-spread">
<span>[3]</span>
<span>2 *</span>
</div>
<div class="flex-spread">
<span>[2, 3]</span>
<span>*</span>
</div>
<div class="flex-spread">
<span>[6] <==</span>
<span></span>
</div>
</details>
</fieldset>
<fieldset class="docs">
<legend>Example programs</legend>
<details>
<summary>Factorial</summary>
<NavLink
href="/concat?in=FwAgxg9grgdgLgUwE4lQEygBxAJhAZwHcBDbAWhAG4AoUAQlRA2wEYQLJZEV8BrAS2wMAVFWoB2EHWpA">
Replace program
</NavLink>
<pre>
: counter dup 2 swap - ;
: ! dup 1 - counter skip ! * ;
7 !
</pre>
</details>
</fieldset>
</main>
|
