[HOpenGL] Newbie: Difference between $= and <- operators?

[Jeff Heard]

the $= only works for OpenGL state variables, whereas <- won't work
for them.  The difference is that $= is implemented by every member of
the SettableStateVar class differently, so that there may be extra
functionality going on under the hood.  The <- operator on the other
hand always has the same meaning (relatively speaking -- it's possible
to override this), in that it is a substitude for

a <- someAction

is the same as

someAction >>= \a -> {- the rest of the do expression -}

-- Jeff

2009/3/20 Mark Spezzano <mark.spezzano at chariot.net.au>:
> Hi,
>
>
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> What is the difference between the $= operator and the <- operator
>
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> Both seem to read “assign to” but surely there is a difference.
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> What should I use when?
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> I want to create an animation that reads some coordinate (state-ful) data.
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> Should I use $= or <- ?
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> Cheers,
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> Mark Spezzano
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>
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