lists

Lists

By default, a HS variable is created as a list, which means that it can have zero, one, or many values, where each value in the array can be of any of the supported data types, including list.

The expression:

a = { 99, 1.23, "mystring" };

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creates a list variable a with the values 99, 1.23, and "mystring". In its most explicit form, the above statement is equivalent to:

list 'a' = { int (99), float (1.23), str ("mystring") };

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The sizes of lists are dynamic. For example, the contents and size of the variable a can be easily changed:

a = { 1, 2, 3, 4, 5};

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We can also change the size of _a _using the following statement:

list a[3]; /* Truncate the list so that it has only 3 values */

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The size of a list (or [vector][0]) can be found using the [count][1] method:

a_size = count ( a );

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An individual list element can be accessed or changed using subscripts.

/* Print subscripted values */
for ( int i=0; i<a_size; i++ ) put ( a[i] );`

/* Assign a subscript value */ a[0] = 66;

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## Strings and Lists

A _str _variable is a special case of a _list_ variable where all 
the elements are of type _str_. In the above example, if the variable _a_
is converted to type _str_, all the values in the list become type _str_:

str a;

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converts the elements of the _list_ to { "99", "1.23", "mystring" }. The 
original _list _can be restored easily enough:

list a;

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converts the _str_ elements back to the original _list_ elements { 
99, 1.23, "mystring" }.


[0]: /docs/language/vectors.php
[1]: http://www.abinition.com/cgi-bin/dofunction.cgi?function=count