Module format 

Printf-style formatting node.

Takes a format string and N inputs, produces a formatted String. Uses {} placeholders (Rust-style, not C printf-style), with optional format specifiers.

Supported specifiers:

• {} — default display
• {:05} — zero-padded to width 5 (u64)
• {:.2} — 2 decimal places (f64)
• {:x} — lowercase hex (u64)
• {:X} — uppercase hex (u64)
• {:b} — binary (u64)
• {:o} — octal (u64)

printf takes a Const<&str> format string, a #[poly_const] cached ParsedFormat, and &[Value] variadic wires. The cached ParsedFormat is computed once at construction (in the parse_format setup-fn) so per-eval work is just iterating the pre-parsed segments.

Structs

FormatSpec

One placeholder’s formatting: which argument, and how to render it.

ParsedFormat

Pre-parsed format string cached on the Printf node. The #[polydat_node] macro invokes parse_format once at construction; eval reads the segments directly with no per-call parsing.

Printf

Printf-style N→1 formatting node. Variadic: accepts 0..N wire inputs.

Enums

FmtArg

One argument to a format, as the formatter needs it: a scalar by value, a string by reference, anything else as the Value whose display form is used. The P1 node builds these from its Value inputs so a string argument is formatted without being copied first.

Segment

A parsed format segment: either literal text or a placeholder.