is_scalar() — internals

is_scalar() — internals

Where it lives

• Signature: src/builtins/types/is_scalar.rs
• Lowering: src/codegen/lower_inst/builtins.rs:1652 (lower_is_scalar)
• Function symbol: lower_is_scalar()

Lowering notes

• Lowers is_scalar(): true for int/float/string/bool, a non-null tagged scalar, or a boxed
• Mixed/Union value whose runtime tag is int (0), string (1), float (2), or bool (3). Null,
• arrays, objects, and resources are not scalars, matching PHP.

Runtime helpers

No direct __rt_* helpers captured — the lowering is inlined or routes through another builtin.

Signature summary

function is_scalar(mixed $value): bool

What the type checker enforces

• Arity: takes exactly 1 argument.

Eval interpreter (magician)

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

Cross-references

• User reference for is_scalar()