pub const PARSE_STACK_SIZE: usize = _; // 16_777_216usizeExpand description
Native stack a thread needs to parse any source the parser accepts.
The parser recurses once per nesting level, and an unoptimized build spends
about 140 KiB of stack on each level of nested expressions. Rust’s 2 MiB
default thread stack is exhausted after about a dozen levels, long before
MAX_NESTING_DEPTH refuses the source, and a stack overflow aborts the
whole process rather than failing one parse. Any thread that runs the parser
and was not created with at least this much stack must ask for it, as
harn_modules’ parallel module loader does.
The size follows the refusal, not the typical program: the parser must be
able to reach MAX_NESTING_DEPTH and report it. RUST_MIN_STACK does
not substitute: CI test lanes export it and no shipped binary does.