map[K]V, [:] and ["a": 1] literals, m[k] reads and writes (m[k] += 1 starts from
zero), has/get/remove/clear/keys/values, .len, copy and printing, and a loop over
a map that stops with an error when it adds keys. for i, x in list gives the
index too.
boot.sh: 17 passed, 0 failed, 5 skipped (all five import C).
A function that can fail returns { ok, value, message }. return error(...) makes
the failure; try passes it on after running the defers; 'or <value>' and
'or { ... err ... }' handle it. int(text), float(text), read_file, write_file
and delete_file report failure to an enclosing or/try instead of stopping the
program. fn main() -> ! prints the error and exits with 1.
boot.sh: 15 passed, 0 failed, 7 skipped.
defer runs when its scope ends and before return, break and continue leave it,
newest first, and sees only the variables declared before it. Not allowed
inside a defer: defer, return, break, continue.
boot.sh: 14 passed, 0 failed, 8 skipped.
Methods are functions whose first parameter is the receiver's address; a method
that changes self can't be called on a temporary or a read-only value, and
calling one on a variable keeps a parameter from being borrowed. An argument
that lives inside the receiver is copied (c.merge(c)). str(x) and print of
arrays and structs go through one formatter, as in the C++ compiler.
boot.sh: 12 passed, 0 failed, 10 skipped.
The self-hosted compiler now has the numeric types the C++ one has: int and
float stay the i64 and f64 defaults, the others lower to their LLVM sizes;
literals adapt to the other operand if they fit, smaller types widen into
bigger ones, signed and unsigned mixing is refused, division and shifts and
comparisons pick their signedness, and u8(x), f32(x), bool(x) convert.
boot.sh: 11 passed, 0 failed, 10 skipped (was 9 / 12).
- fn Struct.method(...) with self by reference, also on C structs
- map[K]V: insertion-ordered hash maps, literals, m[k] += 1, has/get/remove/keys/values
- -> T! / -> !, return error(...), or <value>, or { err }, try; fallible int/float/read_file/write_file/delete_file
- for i, x in list / for k, v in map
- print and str() share one text formatter
- LSP: method and map completion, method signatures; grammar and snippets for VS Code and Kate
- tests: 74 (methods, errors, maps + 11 failure cases); docs at all three levels, en and pl
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
.fn is already used by other tools (e.g. Fennel). Modules are now looked up as name.fch;
a leftover name.fn gets a clear message telling you to rename it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
boot/ is a second Finch compiler written in Finch (lexer, parser, type checker and
an LLVM IR text generator, ~3k lines). Built by the C++ compiler it compiles itself;
stage 2 and stage 3 produce byte-identical IR. It covers the core language: functions,
structs, arrays, str, pointers, loops and modules (no C imports, sized numbers or defer),
copies values like the main compiler and leaves freeing memory to the operating system.
tests/boot.sh checks the fixpoint and runs the test programs it supports.
Also: shell(cmd) built-in.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
