XLISP nth

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# nth

Type: | - | function (subr)
Source: | - | xllist.c

## Syntax

(nth expr list-expr)
  expr - an integer expression
  list-expr - a list or list expression
  returns - the nth element or NIL if the list isn't that long

## Description

'nth' returns the 'expr'-th element of 'list-expr'. If the 'list-expr' is shorter than 'expr', a NIL is returned. The counting sequence is base zero, the first element is the 0th element.

## Examples

    (nth 4 '(0 1 2 3 4 5 6))  ; returns 4
    (nth 3 '(a b))            ; returns NIL

    (nth 4 'a)                ; error: bad argument type
    (nth 3 "abcdefg")         ; error: bad argument type

See the nth function in the XLISP 2.0 manual.

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Nyquist / XLISP 2.0 - Contents | Tutorials | Examples | Reference