They read as design commentary: why a choice was made, what the previous state
of the project was, which library defect a line works around. That is useful to
somebody who already knows the library and useless to somebody trying to build a
game, which is who a tutorial is for.
Both chapters now open with a screenshot of what the reader is building and a
numbered list of the steps to get there, and each step is its own section: what
you are trying to achieve, the code that achieves it, and the two or three things
about that code that are easy to get wrong. Chapter 20 starts from first
principles -- what a sprite, a character, an actor and a tilemap are, and the
four error macros -- and chapter 21 assumes it and covers what a top-down game
adds.
Where a line exists because of a defect, the line comes first and the defect
comes after it, with a pointer to the TODO entry that will remove the need. A
reader who is copying code should not have to read an apology before they can use
it.
The library's own history is gone from both. That belongs in the design chapters
and in git.
Two new docs_examples setups stage the tutorials' own art, so the sprite and
character files a reader is shown are loaded exactly as printed rather than
through a generic fixture. `json excerpt=` is new for the same reason: a Tiled
object is now quoted out of the real map instead of being retyped. Excerpts
across docs/ go from 91 to 137.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KzBDV2fqgnUAcqCKqKvc71
libakgl exports 157 functions and the only user-facing documentation was a FAQ
in README.md whose examples did not compile: two unbalanced `PASS()` calls, a
`sprite->frameids = [0, 1, 2, 3];` that is not C in any dialect, a stray `9`
inside a bitmask expression, an `int screenwidth = NULL`, and -- in the first
snippet a reader ever saw -- the exact `strncpy` call AGENTS.md forbids.
That is not a reader routing around typos. It is what happens to samples that
nothing executes. This is akbasic's documentation harness with the interpreter
taken out and the ability to link and run put in.
The contract is a set of fence info strings, so an example is ordinary markdown
that still highlights on the forge:
```c compiled with -fsyntax-only -Wall -Werror
```c wrap=NAME the same, wrapped in tests/docs_preludes/NAME.pre/.post
```c run=NAME linked against akgl and run headless
```c excerpt=PATH must still appear verbatim in PATH
```c screenshot=NAME also the source of docs/images/NAME.png
```json kind=KIND loaded through the real akgl_*_load_json
```output the exact stdout of the runnable block above it
`run=` is why this links at all: -fsyntax-only proves a call typechecks, not
that the startup order works or that an ATTEMPT block gives back what it took.
`json kind=` exists because the asset formats are documented in prose and read
by four loaders with nothing tying the two together -- util/assets/littleguy.json
is already invalid against the loader it ships with.
A fence with no info string is a hard error, and so is an unknown one. The
failure mode this exists to prevent is passing because it quietly ran nothing,
so an unannotated block is a missing decision rather than a default. Exit status
is the number of failed examples; 2 for a usage error, which is a different
thing and has to be distinguishable.
Proven to fail on all ten of its failure modes -- untagged fence, non-compiling
snippet, stale excerpt, orphan output block, unknown info string, run= output
mismatch, invalid JSON, missing figure, a -Werror warning, and a dangling
preload= -- because a check that has never failed has not been tested.
`-Werror` here although AKGL_WERROR stays off for the library: that option is
off so a new compiler's diagnostic cannot break a consumer's build, and a doc
snippet is not a consumer. A sample that warns is a sample that teaches the
warning.
Registered as `docs_examples` and `docs_screenshots`. No docs-path filter in CI,
deliberately: documentation goes stale because the code moved, not because
somebody edited a chapter.
Co-Authored-By: Claude Code <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
