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Temporal as algebraic effects

A note on the programming-language-theory framing of Temporal — for a reader who writes Python/Go/Java daily but has not had to think about delimited continuations or effect handlers as language features.

Effects, in the PL sense

In a PL-theory context an effect is anything a function does besides return a value: read or write a variable, throw an exception, do I/O, sleep, log, fork. A pure function (input → output, no effect) is the easy case. Languages add effects in different ways: Java has unchecked I/O and checked exceptions; Python has implicit I/O and raise; Go has panic/recover and channels. Effects are how programs actually do anything useful.

The interesting question for PL designers is: can you make effects first-class — values that the language can pass around, intercept, replace? Most mainstream languages do this for one effect (exceptions, via try/catch) and not for the rest.

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Bayesian Frameworks in Cognitive Science and Computer Vision

A conversation about the free energy principle, predictive processing, and how these theoretical frameworks compare to practical engineering approaches in robotics and autonomous vehicles.

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Q: Are you familiar with explanations and theories in cognitive science involving "free energy"?

Yes, I'm quite familiar with this area. The free energy principle (FEP) is a theoretical framework developed primarily by Karl Friston, a neuroscientist at UCL, that attempts to provide a unified account of brain function, perception, action, and learning.

dandavison

<script type="text/x-template" id="vue-file-agent-demo">
  <div>
    <VueFileAgent
      :uploadUrl="'https://www.mocky.io/v2/5d4fb20b3000005c111099e3'"
      :uploadHeaders="{}"
      :multiple="true"
      :deletable="true"
      :editable="true"
      :meta="true"
      :accept="'image/*,video/*,.pdf,.zip'"

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fn prepare(line: &str) -> String {
    if !line.is_empty() {
        let mut line = line.chars();
        let prefix = line.next().unwrap();
        let output_line = line.collect::<String>();
        format!("{}{}", prefix, output_line)
    } else {
        "<empty line>".to_string()
    }
}

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#!/usr/bin/env python

from scipy.optimize import bisect


def record_optimization(func):

    def recorder(self, *args, **kwargs):
        if not hasattr(self, '_recorder_inputs'):
            self._recorder_inputs = []

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#!/bin/bash
set -e

# DOWNLOAD SOURCES FOR LIBEVENT AND MAKE AND INSTALL
curl -OL https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
tar -xvzf libevent-2.0.21-stable.tar.gz
cd libevent-2.0.21-stable
./configure --prefix=/usr/local
make
sudo make install

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Two columns satisfy a "one-to-one" constraint if each value in column 1 is associated with exactly one value in column 2, and vice versa. E.g. in this data, the person column and the email column satisfy a one-to-one constraint:

>>> table = [('pablo', '[email protected]'),
             ('georgia', '[email protected]'),
    	     ('mark', '[email protected]')]
>>> is_one_to_one(table)

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width = 500
height = 300

cube =
    nodes: [
        {x: 0, y: 0, z:0},
        {x: 0, y: 0, z:1},
        {x: 0, y: 1, z:0},
        {x: 0, y: 1, z:1},
        {x: 1, y: 0, z:0},