# head

Definition: | sequence res = head(sequence src, integer size=1)
Description: | Return the first `size` elements of `src`. src: the sequence from which elements will be obtained. size: number of elements required. If omitted, returns src[1..1]. Returns a sequence containing the first `size` elements of src, unless it is shorter than size, in which case src is returned unaltered.
pwa/p2js: | Supported.
Comments: | NB when size is omitted this returns src[1..1] rather than src[1].
Example: |
    s2 = head("John Doe", 4)                -- s2 is John
    s2 = head("John Doe", 50)               -- s2 is John Doe
    s2 = head({1, 5.4, "John", 30}, 3)      -- s2 is {1, 5.4, "John"}
    s2 = head({1, 2, 3, 4})                 -- s2 is {1}
Implementation: | See builtins\pseqc.e (an autoinclude) for details of the actual implementation.