Struct EvaluationResult 

#[non_exhaustive]
pub struct EvaluationResult {
    pub description: String,
    pub mime_type: Option<String>,
    pub confidence: f64,
    pub matches: Vec<RuleMatch>,
    pub metadata: EvaluationMetadata,
}

Result of magic rule evaluation

Contains the file type description, optional MIME type, confidence score, individual match details, and evaluation metadata.

Relationship to crate::output::EvaluationResult

This is the library-facing result type returned by MagicDatabase::evaluate_file and MagicDatabase::evaluate_buffer. It carries a rolled-up description, MIME type, and confidence score along with raw evaluator::RuleMatch values. It intentionally does not carry the analyzed filename or a surface-level error string, because those are caller concerns (a caller may evaluate an in-memory buffer that has no filename).

The parallel type crate::output::EvaluationResult is the output-facing result used by the CLI and JSON/text formatters. It adds filename and error, carries enriched crate::output::MatchResult values (with extracted tags), and uses u32 counters in its metadata to match the JSON output schema.

The two types are intentionally distinct — do not try to unify them. Convert library → output explicitly via crate::output::EvaluationResult::from_library_result, which is the single named conversion point. Any drift between the two hierarchies should be resolved there, not by back-channel field copying in call sites.

Examples

use libmagic_rs::{EvaluationResult, EvaluationMetadata};

let result = EvaluationResult::new(
    "ELF 64-bit executable".to_string(),
    Some("application/x-executable".to_string()),
    0.9,
    vec![],
    EvaluationMetadata::default(),
);

assert_eq!(result.description, "ELF 64-bit executable");
assert!(result.confidence > 0.5);

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

description: String

Human-readable file type description

This is the concatenated message from all matching rules, following libmagic behavior where hierarchical matches are joined with spaces (unless backspace character is used).

mime_type: Option<String>

Optional MIME type for the detected file type

Only populated when enable_mime_types is set in the configuration. Omitted from the serialized form when unset (rather than emitted as "mime_type": null) so downstream JSON consumers can treat presence as the “MIME type is known” indicator.

confidence: f64

Confidence score (0.0 to 1.0)

Based on the depth of the match in the rule hierarchy. Deeper matches indicate more specific identification.

matches: Vec<RuleMatch>

Individual match results from rule evaluation

Contains details about each rule that matched, including offset, matched value, and per-match confidence.

metadata: EvaluationMetadata

Metadata about the evaluation process

Implementations

impl EvaluationResult

pub fn new( description: String, mime_type: Option<String>, confidence: f64, matches: Vec<RuleMatch>, metadata: EvaluationMetadata, ) -> Self

Construct a new library-side EvaluationResult.

This is the outbound type returned by MagicDatabase::evaluate_file and MagicDatabase::evaluate_buffer. For the output-facing type used by the CLI and JSON/text formatters, see crate::output::EvaluationResult::from_library_result.

Trait Implementations

impl Clone for EvaluationResult

fn clone(&self) -> EvaluationResult

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EvaluationResult

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Serialize for EvaluationResult

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.