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17 guides
Coldwast wrote
Aug 12, 2026 in Haskell, Types, Concepts - Haskell signatures look cryptic until you know the three rules that govern them: the arrow groups to the right, lowercase names are variables, and the fat arrow is not an argument. Read left to right, with worked examples.
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Aug 10, 2026 in Haskell, Tooling, Search - Hoogle searches the Haskell libraries by function name and, unusually, by type signature. How type search works, the query syntax that matters, how to scope results to your own dependencies, and when to run it locally.
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Aug 4, 2026 in Haskell, Cabal, Build - Adding a package to a Haskell project means editing build-depends in the .cabal file. What the field expects, what the caret operator really means under the Package Versioning Policy, and why cabal update matters before anything else.
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Jun 24, 2026 in Programming, Concepts, Haskell - A higher-order function takes a function as an argument or returns one as its result. What higher-order functions are, why map, filter and fold are the classic examples, how they replace loops, and how they work in Haskell.
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Jun 15, 2026 in Programming, Concepts, Haskell - Functional programming is a style built on pure functions, immutability and treating functions as values. Its core ideas, how it differs from imperative/OOP code, the trade-offs, and where Haskell fits.
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Jun 14, 2026 in Haskell, Concepts - Haskell is a purely functional, statically typed, lazy language with powerful type inference. The ideas that define it - purity, immutability, laziness, strong types - what it is used for, and how to start.
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Jun 14, 2026 in Haskell, Syntax - A list comprehension builds a list from generators with optional guards - concise and close to set-builder notation. Syntax, multiple generators, guards, and how they relate to map and filter.
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Jun 14, 2026 in Haskell, Concepts - Haskell computes a value only when it is actually needed. What lazy evaluation is, thunks, infinite data structures, the space-leak trap, and forcing strictness with seq and BangPatterns.
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Jun 14, 2026 in Haskell, Concepts - A monad sequences computations carrying context - Maybe, Either, IO, lists. What it really is, bind (>>=) and return, and do-notation, plainly.
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Jun 14, 2026 in Haskell, Compiler - What GHC is, installing it with GHCup, using GHCi, the flags that matter (-O2, -Wall, -threaded, -j), and how it fits with Cabal and Stack.
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Jun 14, 2026 in Haskell, Editor - What HLS does, installing it with GHCup, wiring it into VS Code and Neovim, matching it to your GHC, and fixing the usual errors.
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Jun 14, 2026 in Haskell, Toolchain - GHCup is the recommended way to install GHC, Cabal, Stack and HLS in 2026 - clean install, version switching, and the common pitfalls that trip newcomers.
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Jul 31, 2026 in Haskell, Rust, Languages - Haskell and Rust both promise correctness through the type system, then diverge completely on memory. Garbage collection versus ownership, lazy versus strict, and which question each one actually answers.
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Jun 14, 2026 in Haskell, Cabal, Build - Cabal and Stack are the two main ways to build Haskell projects. What each one is, how they differ (Hackage vs Stackage, reproducibility, GHC management), the equivalent commands, and how to choose in 2026.
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Jun 13, 2026 in Haskell, Cabal, Build - The per-project isolation idea that won so completely it became invisible. What sandboxes were, and the nix-style cabal build workflow that superseded them.
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Jun 13, 2026 in Haskell, Cabal, Build - Nix-style builds, Backpack, the caret operator and a better solver - what 2.0 introduced and where each feature stands in the 2026 toolchain.
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Jun 13, 2026 in Haskell, Performance - Why a build is a dependency graph, how -j builds use your cores, and the modern job-semaphore fix for oversubscription on wide dependency trees.
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