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<head><title>runLengthEncode(VisibleList) -- run length encoding</title>
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<div><h1>runLengthEncode(VisibleList) -- run length encoding</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>runLengthEncode x</tt></div>
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<li><span>Function: <a href="_run__Length__Encode_lp__Visible__List_rp.html" title="run length encoding">runLengthEncode</a></span></li>
<li><div class="single">Inputs:<ul><li><span><tt>x</tt>, <span>a <a href="___Visible__List.html">visible list</a></span></span></li>
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<li><div class="single">Outputs:<ul><li><span>a list equivalent to <tt>x</tt>, in which runs and sequences have been expressed symbolically as <a href="___Expression.html">expressions</a></span></li>
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<div class="single"><h2>Description</h2>
<div><p>The result is useful in printed displays, as a way of making them more compact. The original list can be recovered by appying <a href="_value.html" title="evaluate">value</a> to the elements of the result, and then using <a href="_deep__Splice.html" title="remove subsequences">deepSplice</a>, provided that <tt>x</tt> contains no entries that are sequences.</p>
<table class="examples"><tr><td><pre>i1 : x = {1,2,3,a,b,c,a,b,c,4,4,4,"asdf"};</pre>
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<tr><td><pre>i2 : y = runLengthEncode x
o2 = {1..3, 2:a..c, 3:4, asdf}
o2 : List</pre>
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<tr><td><pre>i3 : peek y
o3 = {BinaryOperation{.., 1, 3}, BinaryOperation{:, 2, a..c},
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BinaryOperation{:, 3, 4}, Holder{asdf}}</pre>
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<tr><td><pre>i4 : value \ y
o4 = {(1, 2, 3), ((a, b, c), (a, b, c)), (4, 4, 4), asdf}
o4 : List</pre>
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<tr><td><pre>i5 : deepSplice \\ oo
o5 = {1, 2, 3, a, b, c, a, b, c, 4, 4, 4, asdf}
o5 : List</pre>
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<tr><td><pre>i6 : x === oo
o6 = true</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___Binary__Operation.html" title="the class of all binary operation expressions">BinaryOperation</a> -- the class of all binary operation expressions</span></li>
<li><span><a href="___Holder.html" title="the class of all holder expressions">Holder</a> -- the class of all holder expressions</span></li>
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