"do" as a keyword

[BJörn Lindqvist]

On Dec 11, 2007 4:06 PM, Neil Cerutti <horpner at yahoo.com> wrote:
>
> However, did you have an specific need for a do-while construct?
> Perhaps we could show you the alternatives.

I have wanted do-while loops in exactly one kind of algorithms, when
you generate something and you have to keep trying until it gets
right. For example, generating random and non-overlapping points on a
grid:

    import random
    grid = dict()
    for i in range(10):
        while True:
            x = random.randint(0, 4)
            y = random.randint(0, 4)
            if not (x, y) in grid:
                break
        grid[x, y] = 1

The loop runs one or more times until a vacant spot in the grid is
found. This type problem would be better expressed using a do-while:

    import random
    grid = dict()
    for i in range(10):
        do:
            x = random.randint(0, 4)
            y = random.randint(0, 4)
        while (x, y) in grid
        grid[x, y] = 1


-- 
mvh Björn