ferogram_tl_parser/tl/parameter.rs
1// Copyright (c) Ankit Chaubey <ankitchaubey.dev@gmail.com>
2// SPDX-License-Identifier: MIT OR Apache-2.0
3//
4// ferogram: async Telegram MTProto client in Rust
5// https://github.com/ankit-chaubey/ferogram
6//
7// If you use or modify this code, keep this notice at the top of your file
8// and include the LICENSE-MIT or LICENSE-APACHE file from this repository:
9// https://github.com/ankit-chaubey/ferogram
10
11use std::fmt;
12use std::str::FromStr;
13
14use crate::errors::ParamParseError;
15use crate::tl::ParameterType;
16
17/// A single `name:Type` parameter inside a TL definition.
18#[derive(Clone, Debug, PartialEq, Eq, Hash)]
19pub struct Parameter {
20 /// The parameter name as it appears in the TL schema.
21 pub name: String,
22 /// The resolved type of this parameter.
23 pub ty: ParameterType,
24}
25
26impl fmt::Display for Parameter {
27 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
28 write!(f, "{}:{}", self.name, self.ty)
29 }
30}
31
32impl FromStr for Parameter {
33 type Err = ParamParseError;
34
35 /// Parses a single parameter token such as `flags:#`, `id:long`, or
36 /// `photo:flags.0?InputPhoto`.
37 ///
38 /// Returns `Err(ParamParseError::TypeDef { name })` for the special
39 /// `{X:Type}` generic-parameter-definition syntax so callers can handle it
40 /// without the overhead of `?`.
41 fn from_str(token: &str) -> Result<Self, Self::Err> {
42 // Generic type-definition `{X:Type}`: not a real parameter
43 if let Some(inner) = token.strip_prefix('{') {
44 return Err(match inner.strip_suffix(":Type}") {
45 Some(name) => ParamParseError::TypeDef { name: name.into() },
46 None => ParamParseError::MissingDef,
47 });
48 }
49
50 let (name, ty_str) = token
51 .split_once(':')
52 .ok_or(ParamParseError::NotImplemented)?;
53
54 if name.is_empty() || ty_str.is_empty() {
55 return Err(ParamParseError::Empty);
56 }
57
58 Ok(Self {
59 name: name.to_owned(),
60 ty: ty_str.parse()?,
61 })
62 }
63}