Skip to main content

Module fmt

logicaffeine_data

Module fmt 

Source
Expand description

The ONE float-display path.

Every engine that renders a LOGOS Float — the tree-walker, the bytecode VM, the AOT-compiled binary, and the direct-WASM host — must agree on the decimal string for the same f64, or the same program prints different answers depending on how it was run. This module is the single authority.

The contract of fmt_f64:

  • Shortest round-trip: the fewest decimal digits that parse back to the exact same bits (Rust’s {} Display, Grisu/Dragon in std). A typed literal echoes as typed; 1.0 / 3.0 shows all 17 significant digits.
  • Never scientific notation: 0.0000001 renders as 0.0000001, not 1e-7 — and a nonzero value NEVER renders as 0.
  • Integral floats stay bare: 2.0 renders as 2.
  • Bounded width: the longest possible output (the smallest subnormal, 5e-324) is under 340 bytes — the direct-WASM host’s scratch size.

Functions§

fmt_f64
Renders an f64 exactly as LOGOS displays it on every engine.