Versions

At the moment, Johann is building up from "nothing" towards "enough". There's still a lot of kludge, but gone are the days of "anything is better than writing assembly."

For now, there only two constraints on versioning:

The current release can compile the development sources.
The development sources can compile themselves.

This provides a backwards compatibility guarantee for a single release. Skipping a release may break things. For example, upgrading to v0.20250610 introduced == and deprecated =. Support for = (as a comparison operator) wasn't removed until v0.20250613.

A few things remain before 1.0:

A syntactic revision, including function return types.
The compilation pipeline itself has two major shortcomings:
1. typechecks are half during parsing and half during codegen, and
2. codegen is direct from the parse tree, without an intermediate representation (aka "three address codes").
Some way to deal with varargs (for printf). io is the last bit of non-syscall assembly, as it still can't be implemented in Johann.

Release History

`v0.20251224`

Numerous small bug fixes, post AoC: clarify %'s result's sign, better errors on mis-freed memory and from ArrayList, drop for StringBuilder, and add drop to the Iterator protocol.

`v0.20251201`

Add a MIN_INTEGER global.

`v0.20251130`

Add a MAX_INTEGER global, and a pow function.

Support -2^63 as a literal value.

Remove %o support from printf, and format the null pointer as NUL (not 0x0).

`v0.20251129`

Include jstdlib.jnh next to jstdlib.o.

Support logical && and || operators, and the four bitwise operators

`v0.20251128`

Iterator convention, and implement for ArrayList and HashMap's keys.

Functions can have any number of formal args, and calls can pass any number of params, including to printf.

Nesting more than eight levels deep no longer causes memory corruption.

`v0.20251122`

Massive performance gains in the allocator, particularly for free.

Logical shift operators << and >>, for reasonable operands.

printf pads numbers with spaces by default, instead of zeros, and no longer supports %n (for newline).

`v0.20251121`

else and else if are supported!

HashMap supports pointer-identity internally, so callers don't have to do it explicitly.

The standard library's collection types' "drop" functions accept null (like free does).

`v0.20251116`

Remove the sequential-scan table type; HashMap and TreeMap are better.

Allow redeclaring variables w/ the same type.

--header no longer implies --strict. Too annoying to set up the build chains.

`v0.20251115`

Add StringBuilder_into_int to ease memory management.

Unlimited local variables, instead of being capped at eight.

Add calloc, mostly for auto-zeroed memory (not array allocations).

Fix a couple allocation defects, one mis-allocating on page boundaries, one on recycling freed chunks.

`v0.20251109`

Allow redeclaring (but not redefining) structs. Formal args can only use declared types. Include variables in headers. Alphabetize all members in the johanndocs.

Add a --strict option to jnc to fail on unknown function calls; you'll need header file(s) for multi-file projects. Using --header implies --strict.

`v0.20251108`

Add check that calls to declared functions pass the right number of params (types are not checked). Calls to undeclared functions are not checked. Don't require a declaration to take a function pointer. Add checks that function redeclarations are compatible, and disallow redefining.

Add a --header option to jnc to emit a Johann source file containing the compilation unit's pub declarations (aside from main).

`v0.20251106`

Add a length "method" to StringBuilder. Reinstate itoa and add its complement atoi as well.

`v0.20251104`

Add a new HashMap type, along with strhash which computes a hash for a NTSB. Index docs by declaration, not just file, and break some of the large pages into smaller ones.

`v0.20251103`

Add a Queue type. Quicksort as a platform routine, with sorting ArrayList based on it. Several new string functions: strstr, strsplit, strjoin. Support setting an ArrayList element, and reserving capacity.

`v0.20251029`

Pseudo-method invocation, so StringBuilder_push(sb, 'c') becomes sb.push('c'), assuming sb is declared StringBuilder*. Add ArrayList_push_all, strchr, and substr to jstdlib.

`v0.20251026`

Add array-ish syntactic sugar for pointer arithmetic, though not actual arrays or array types. Add a read_line function to io. Add push_str method to StringBuilder.

`v0.20250622`

Use structs a couple places, fix an assignment ordering bug.

`v0.20250620`

Add struct declarations, and support variable declarations of struct types. A new . operator provides access to members of a pointed-to struct for both reading and writing.

`v0.20250613`

Add ArrayList and TreeMap ADTs to the library. Remove support for = and ! as comparison operators. Parse full programs, not just expressions.

`v0.20250610`

Support == and != in favor of their kludge counterparts = and !. Support >= and <= as well. Use "best fit" memory recycling, instead of "lowest address". Add actual docs, not a 20-page README.md.

`v0.20250607`

Support compound expressions with a proper parser; statements and declarations are parsed, but still emitted from the token stream.

`v0.20250606`

jnc is entirely Johann, and memory error reporting is further improved.

`v0.20250530`

Add StringBuilder to the library, convert more of jnc to Johann, and support function pointers (via declarations).

`v0.20250526`

Fix globals to use their declared width. Improve reporting of memory errors.

`v0.20250525`

Recycle freed memory, and get more from the OS as needed. Introduce pub to make symbols available to other compilation units.

`v0.20250524`

First parts of jnc and jstdlib.o written in Johann. Support void returns, hex literals, and taking an address.

`v0.20250522`

Support for writing to global variables, not just reading them.

`v0.20250518`

Lex numbers directly, use printf for emitting, add symbol tracking and extremely primitive register allocation so programs can use symbolic names, rather than just a-h. Still constrained to eight local vars per function.

`v0.20250510`

Add IO functions - including printf - and some character recognition functions. Buffer STDIN & STDOUT. A simple linear-scan map/table/dict.

`v0.20250426`

Add void as a type (for pointers), as well as done/again loop control keywords.

`v0.20250420`

Direct translation to assembly, and direct mapping of single-character variable names to registers (variable a goes in x20, b goes in x21, etc.). Memory is fixed-size and allocate-only, never freed. Sufficient to solve Not Quite Lisp.