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pub type OptTaggedExplicit<T, const TAG: u32> = Option<TaggedValue<T, Explicit, {_: u8}, TAG>>;
Available on crate feature mtls only.
Expand description

A helper object to parse [ n ] EXPLICIT T OPTIONAL

A helper object implementing FromBer and FromDer, to parse tagged optional values.

This helper expects context-specific tags. Use Option< TaggedValue > for a more generic implementation.

Examples

To parse a [0] EXPLICIT INTEGER OPTIONAL object:

use asn1_rs::{FromBer, Integer, OptTaggedExplicit, TaggedValue};

let bytes = &[0xa0, 0x03, 0x2, 0x1, 0x2];

// If tagged object is present (and has expected tag), parsing succeeds:
let (_, tagged) = OptTaggedExplicit::<Integer, 0>::from_ber(bytes).unwrap();
assert_eq!(tagged, Some(TaggedValue::explicit(Integer::from(2))));

// If tagged object is not present or has different tag, parsing
// also succeeds (returning None):
let (_, tagged) = OptTaggedExplicit::<Integer, 0>::from_ber(&[]).unwrap();
assert_eq!(tagged, None);