mb_strlen() — internals

mb_strlen() — internals

Where it lives

• Signature: src/builtins/string/mb_strlen.rs
• Lowering: src/codegen/lower_inst/builtins/strings.rs:374 (lower_mb_strlen)
• Function symbol: lower_mb_strlen()

Lowering notes

• Lowers mb_strlen(string, encoding = null) through the multibyte runtime helper.
• Omitted/null encodings use a null pointer plus zero length; explicit names stay byte strings for PHP-compatible case-insensitive lookup and ValueError handling.

Runtime helpers

The following runtime helpers are referenced:

• __rt_mb_strlen

Signature summary

function mb_strlen(string $string, string $encoding = null): int

What the type checker enforces

• Arity: takes 1–2 arguments (1 optional).

Eval interpreter (magician)

• Declaration: crates/elephc-magician/src/interpreter/builtins/string/mb_strlen.rs (eval_builtin!)
• Dispatch hooks: direct, values

Cross-references

• User reference for mb_strlen()