This page describes how to build an interpreter for most of the scheme dialect of lisp. it uses python 3 as the implementation language, and the lambda special form is a good example of scheme syntax. if you are familiar with other languages, you might think that while or for loop would be needed, but scheme manages to do without these just fine. in which we judge lispy on several criteria: ...
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The game offers real-time simulation with fully simulated projectile ballistics and terrain deformation, allowing for diverse strategies on each map. Players can choose from over 10 unit classes to balance resource income and production for victory.
The Personal Data Server (PDS) in ATProto holds users' signing keys and rotation keys, allowing the operator to impersonate users across all apps in the ecosystem and lock them out of their identities. This centralization of key management makes the system brittle, relying on trusting the PDS operator, and users should be able to enroll self-controlled rotation keys by default to mitigate this risk.
Commodore's Callback 8020 is a smartphone with a Linux-based Sailfish OS, running essential apps without social media or browsers. It's designed for digital minimalism, with a focus on intentional use and a price starting at $500.
The author argues that Geometric Algebra (GA) has flaws that need to be addressed in order for it to succeed, particularly its overemphasis on the geometric product and lack of self-awareness about its limitations. The author believes that GA's underlying concepts, such as multivectors and the wedge product, are valuable but that the GA movement's ideology and framework are problematic and ...
Google's measurements show IPv6 reaching 50% for the first time, but APNIC Labs data shows a 42% worldwide IPv6 capability. IPv6 adoption varies across regions and economies, with some countries like India and Saudi Arabia showing different adoption curves.
This project aims to create a voxel game using APL notation, with installation instructions for macOS and Linux. Compilation on Windows requires SDL3 dev libraries and cmake-gui, with shaders compiled using ./compile_shaders.sh.
The maritime fuel problem is not about replacing fossil fuels with alternative molecules, but about reducing demand due to declining fossil cargo and electrifiable segments growing. Batteries and shore power are suited for inland shipping, ferries, and short-sea routes, reducing the need for alternative fuels.
Loupe is an iOS app that shows device fingerprinting data from public APIs, helping users see what apps can quietly learn about their device. It's free and open source, with a Mac version in development.
A user ported classic GW-BASIC games to C for various platforms. The project is licensed under the MIT License and includes original GW-BASIC code for reference.
My libsystrap library provides a simple instrumentation of system calls in Linux x86-64 userland. However, its current implementation suffers a double-trap overhead: system calls become ud2, which generates a SIGILL trap. Then we run the system call itself from within the signal handler, causing a second trap and some interesting tricky cases. There has been some interesting research in this ...
The user created a Debian package called pve-microvm that adds QEMU's microvm machine type as a first-class managed guest in Proxmox VE, allowing for fast and isolated VMs with a custom kernel and minimal virtio-only environment. The package supports 21 guest OS types, including Linux, NetBSD, and Plan9, and provides features like sub-300ms boot times, virtio devices, and vsock CID for ...
The author set up a DGX Spark with multiple vLLM containers to serve two Qwen3 models, but faced memory issues due to incorrect gpu_memory_utilization settings. The solution involved adjusting the settings to account for CUDA framework overhead and Mamba state alignment.
Finland's libraries are thriving as community service centers, offering more than just books, and promoting social inclusion and democracy. They are valued for their role in helping societies function, with over 700 libraries serving Finland's 5.6 million people.
Prolonged exhalation breathing can increase cardiac parasympathetic activity, leading to enhanced reward sensitivity and increased risky choices. This effect is associated with changes in brain activity in regions involved in reward processing, such as the ventromedial prefrontal cortex and precuneus.
The author experimented with two optimizations for AVX-512 vertex decoding in meshoptimizer, but only one made it in. The first optimization used a branchless formulation to decode zigzag encoded integers, while the second used AVX-512 predication support to compile the branching variant directly.
The user discusses the differences between epoll and io_uring for handling asynchronous I/O on Linux, highlighting io_uring's efficiency and reduced syscall overhead. io_uring is recommended for modern Linux projects due to its improved performance and architectural changes.
macOS uses two path separators: slash (/) and colon (:), inherited from classic Mac OS and Unix. This dual system causes files to appear with slashes or colons in their names, depending on the context.
Web developers often misunderstand how CORS works, leading to security vulnerabilities like the recent Zoom vulnerability, which was caused by bypassing CORS to access a localhost webserver. A secure implementation would involve implementing a REST API with CORS headers and a Content Security Policy to prevent unauthorized access.
A rare 15th-century rotating bookmark sold for £7,000, six times its high estimate. It features a parchment disc with Arabic numerals and symbols, used by a scribe to keep track of writing columns.
SMPTE has made its entire Standards catalog freely available to the global media technology community. This move aims to accelerate adoption and implementation, strengthen interoperability, and drive innovation in the industry.
Bayer AG developed the Preclinical Information Center (PRINCE) platform to address pharmaceutical industry challenges in drug development, leveraging Agentic Retrieval-Augmented Generation and Text-to-SQL to integrate decades of safety study reports. PRINCE evolved from a keyword-based search tool to an intelligent research assistant capable of answering complex questions and drafting ...
The F-15 Strike Eagle 2 reconstruction project has made significant progress, with all C code rewritten and data moved from assembly to C. The project is now open for testing and bug reporting, with the latest release v0.9.1 available for download.
LymeAlert is a 15-minute tick test that can detect Lyme disease, priced at $40 per test. It's designed to help people avoid unnecessary doctor visits and antibiotic doses by testing ticks for the disease.
Unauthorized alert with "misantropi4" message sent to cell phones in Brazil, suspected to be a hacker attack. Brazilian government is investigating the incident and restoring the National Civil Defense's warning platform.
visionOS receives X11 calls from clients and vintage machines, opening each top-level window separately. X authority cookies are generated on device and copied to clients for secure connections.
The user explored how Windows handled opening non-executable files from 1989's Windows 386/2.11 to 2015's Windows 10, noting changes in file type association UI and functionality. The user observed a shift from basic dialogs to more complex and flat interfaces, with varying levels of interactivity and options for selecting programs to open non-executable files.
A PID controller is a feedback-based control loop mechanism used in industrial control systems to manage machines and processes with continuous control and automatic adjustment. It compares the desired target value with the actual value of the system and applies corrective actions to bring the system to the desired setpoint using proportional, integral, and derivative methods.
The user built a 4-bit CPU kit called TD4 from Aliexpress, which has 2 registers, LEDs, and 16 bytes of program ROM, and wrote notes to help others understand its architecture and usage. The user encountered some difficulties during assembly, including soldering the USB connector and understanding the directionality of surface mount diodes, but eventually got the CPU working and wrote a ...
Researchers developed a new system for whole cross-sectional ultrasound tomography, enabling imaging of the entire human cross-section in reflection and transmission modes. This system has potential applications in clinical needs, such as adipose thickness assessment and video-rate biopsy needle localization.