author | Matthew Wild <mwild1@gmail.com> |
Fri, 13 Jan 2012 23:30:00 +0000 | |
changeset 4466 | 28e0bf9cf0f5 |
parent 4362 | 851885cb332d |
child 4467 | fc8a22936b3c |
permissions | -rw-r--r-- |
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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local gettime = require "socket".gettime; |
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util.throttle: Import setmetatable
Matthew Wild <mwild1@gmail.com>
parents:
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local setmetatable = setmetatable; |
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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module "throttle" |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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local throttle = {}; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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local throttle_mt = { __index = throttle }; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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function throttle:update() |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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local newt = gettime(); |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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local elapsed = newt - self.t; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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self.t = newt; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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local balance = self.rate * elapsed + self.balance; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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if balance > self.max then |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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self.balance = self.max; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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else |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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self.balance = balance; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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return self.balance; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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function throttle:peek(cost) |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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cost = cost or 1; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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return self.balance >= cost or self:update() >= cost; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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changeset
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function throttle:poll(cost, split) |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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if self:peek(cost) then |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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self.balance = self.balance - cost; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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return true; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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else |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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local balance = self.balance; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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if split then |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
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self.balance = 0; |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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return false, balance, (cost-self.balance); |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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function create(max, period) |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
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return setmetatable({ rate = max / period, max = max, t = 0, balance = max }, throttle_mt); |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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end |
851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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851885cb332d
util.throttle: Generic module by waqas to limit something over some time
Matthew Wild <mwild1@gmail.com>
parents:
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return _M; |