8a19f60386
- Reorder README to have implementation list after "learning tool" bullet. - This also moves tests/ and libs/ into impls. It would be preferrable to have these directories at the top level. However, this causes difficulties with the wasm implementations which need pre-open directories and have trouble with paths starting with "../../". So in lieu of that, symlink those directories to the top-level. - Move the run_argv_test.sh script into the tests directory for general hygiene. |
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|---|---|---|
| .. | ||
| core.asm | ||
| Dockerfile | ||
| env.asm | ||
| exceptions.asm | ||
| macros.mac | ||
| Makefile | ||
| printer.asm | ||
| reader.asm | ||
| README.md | ||
| run | ||
| step0_repl.asm | ||
| step1_read_print.asm | ||
| step2_eval.asm | ||
| step3_env.asm | ||
| step4_if_fn_do.asm | ||
| step5_tco.asm | ||
| step6_file.asm | ||
| step7_quote.asm | ||
| step8_macros.asm | ||
| step9_try.asm | ||
| stepA_mal.asm | ||
| system.asm | ||
| types.asm | ||
x86_64 NASM implementation
Notes and known issues:
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No library dependencies, only Linux system calls
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Simple readline implemented, just supporting backspace for editing
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Reference counting used for memory management. No attempt is made to find circular references, so leaks are possible. In particular defining a function with def! creates a circular reference loop.
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The exception/error handling just resets the stack and jumps to a handler, so does not release memory
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Memory is allocated by two fixed-size allocators (
ConsandArrayobjects) which have limits specified in types.asm. If more memory is needed then this must currently be done at compile-time, but adding sys_brk calls could be done. -
The hash map implementation is just a list of key-value pairs. Moving symbols around in the core environment makes a significant difference (20-30%) to the performance test. A simple optimisation could be to move items when found to the start of the list so that frequently searched keys are nearer the front.
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conjfunction not yet implemented -
*env*symbol evaluates to current Environment.