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el/docs/v1/experiments/cycles/16-tokens-carry-no-position.md
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bigmerge c6ba0677f0 log v1 experiments: nineteen cycles, organised by the method that produced them
cycles/    one file per Ishikawa -> scientific method -> Six Sigma loop, named
           for the DEFECT not the fix, carrying the commit record as written at
           the time
findings/  what the cycles produced, cross-cut: live bugs, architecture answers,
           and defects in my own measurement

The organising finding is that predictions which came back FALSE produced every
significant result. Eleven of sixty-one failed, and those eleven found: that the
arity table was not drifted but 40% incomplete; that the AST traversal is
irreducible and only rules and judgments move; that guards could refuse through
the seam after all; and that routing el_bin_lookup through the gate did NOT fix
the SIGSEGV, because the fallback strlen was the hazard -- a wrong fix I would
otherwise have shipped as verified.

One cycle was run without committing predictions first and had to be discarded
as rigged. It is kept, in full, as 18-async-half-expressible.md.
2026-08-17 10:52:17 -05:00

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# tokens carry no position
One `Ishikawa → scientific method → Six Sigma` loop. The record below is the
commit message as written at the time, before the outcome was known to anyone
reading this file.
## Record — `6c975b1`
```
thread provenance through resolve_imports
The module question ended with a limit: textual inlining destroys file
provenance, so a duplicate-definition message could name the symbol but not the
files. Threading it exposed a bigger absence first.
TOKENS HAD NO POSITION AT ALL. A token was a flat (kind, value) pair, so NO
diagnostic in El could name a place -- every error named a symbol and never a
line. That is the prerequisite the module question was resting on.
THE CHAIN, end to end
lexer counts newlines; tok_append mints (kind, value, line)
parser stride 2 -> 3; tok_line added; FnDef carries its line
codegen records <fn> defines_at:<line>
resolve_imports publishes <file> spans <start> <end> for the combined source
checker maps a combined line back to file:line-within-that-file
duplicate definition: 'helper' is defined 2 times — El has no namespacing,
so imported modules share one global scope
/tmp/modtest/a.el:1
/tmp/modtest/b.el:1
PREDICTIONS AND RESULTS
P1 15 stride sites, encapsulated in tok_kind/tok_value TRUE, but see below
P2 adding a line field is mechanical TRUE
P3 the lexer must count newlines TRUE
P4 resolve_imports can record per-file line ranges TRUE
P5 the message can then name both files TRUE
P6 token memory grows TRUE, 25.0 -> 33.9 MB (+36%)
FOUR DEFECTS, EACH FOUND BY RUNNING AND NOT BY READING
1. interp_tokens_append_all walks the token list DIRECTLY with its own copy of
the stride. Gen1 built fine and gen2 emitted corrupt C, because the
compiler's own source uses string interpolation. My search missed it because
I grepped for the variable name `tokens`; it is called `dst`/`result`.
Searching by name instead of by shape -- third time today.
2. tok_count in test_compiler.el carried the stride too. I had scoped the search
to compiler sources and it had escaped into the tests.
3. Nested resolve_imports calls accumulated spans into shared state, so each
republished meaningless line ranges under the parent's name. Making the
buffer local fixed it; guarding the WRITE did not, which is what I tried
first.
4. The first working version reported b.el:3 -- the COMBINED line against a
filename that has no line 3. A file:line that does not match the file is
worse than no line at all.
105/105 native, 37/37 integration, fixpoint ok, compiler self-checks clean.
```
## Record — `cb7289f`
```
thread provenance end to end: a diagnostic can finally name a place
```