Function from_sexp 

pub unsafe fn from_sexp<T>(x: SEXP) -> T
where
    T: TryFromSexp,
    T::Error: Display,

Convert an R SEXP to a Rust type, aborting via Rf_error on failure.

Attempts TryFromSexp::try_from_sexp and calls rf_error (R longjmp, never returns) if conversion fails.

Type Parameters

• T - Target Rust type (must implement TryFromSexp)

Arguments

• x - R value to convert

Returns

The converted Rust value.

Safety

• x must be a valid SEXP
• Must be called on R’s main thread

Errors

Calls rf_error (never returns) if conversion fails. Error messages are generated by TryFromSexp’s error type’s Display impl.

Example

// In a method shim:
let arg0: i32 = unsafe { from_sexp(argv[0]) };
let arg1: String = unsafe { from_sexp(argv[1]) };