Index? - Function Summary

Summary:

Returns the index number of the current position in the series.

Usage:

index? series

Arguments:

series - The series argument. (must be: series port)

Description:

The index function returns the position within a series. For example, the first value in a series is an index of one, the second is an index of two, etc.

str: "with all things considered" print index? str 1

print index? find str "things" 10

blk: [264 "Rebol Dr." "Calpella" CA 95418] print index? find blk 95418 5

Use the OFFSET? function when you need the index difference between two positions in a series.

Related:

head - Returns the series at its head.
head? - Returns TRUE if a series is at its head.
length? - Returns the length of the series from the current position.
offset? - Returns the offset between two series positions.
pick - Returns the value at the specified position in a series.
skip - Returns the series forward or backward from the current position.
tail - Returns the series at the position after the last value.
tail? - Returns TRUE if a series is at its tail.