27 lines
578 B
Markdown
27 lines
578 B
Markdown
# 37-haskell-transformer-stack
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This example shows intermediate Haskell effect composition with a transformer stack.
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It includes:
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- a rollout environment carried by `ReaderT`,
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- explicit rollout failures carried by `ExceptT`,
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- ordered audit lines carried by `Writer`,
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- one stacked workflow that validates and renders a rollout summary, and
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- a test suite run by `nix flake check`.
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Useful commands:
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```bash
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nix develop
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cabal run
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cabal run -- api:production:4
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cabal test
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nix build
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./result/bin/mini-stack api:production:4
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nix run . -- api:production:4
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nix flake check
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```
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