syn_utils/
expr_trait.rs

1use crate::*;
2
3pub trait ParseExpr {
4  fn parse_string(&self) -> syn::Result<String>;
5  fn parse_path(&self) -> syn::Result<&Path>;
6  fn parse_int<N>(&self) -> syn::Result<N>
7  where
8    N: FromStr,
9    N::Err: Display;
10  fn parse_closure(&self) -> syn::Result<&ExprClosure>;
11  fn parse_call_or_closure(self) -> syn::Result<CallOrClosure>;
12  fn parse_call(&self) -> syn::Result<&ExprCall>;
13}
14
15impl ParseExpr for Expr {
16  fn parse_call(&self) -> syn::Result<&ExprCall> {
17    if let Expr::Call(call) = self {
18      Ok(call)
19    } else {
20      Err(error!(self, "Expected a function call"))
21    }
22  }
23  fn parse_string(&self) -> syn::Result<String> {
24    if let Expr::Lit(expr_lit) = self && let Lit::Str(value) = &expr_lit.lit {
25      Ok(value.value())
26    } else {
27      Err(error!(self, "Expected a string literal"))
28    }
29  }
30
31  fn parse_path(&self) -> syn::Result<&Path> {
32    if let Expr::Path(expr_path) = self {
33      Ok(&expr_path.path)
34    } else {
35      Err(error!(self, "Expected a path"))
36    }
37  }
38
39  fn parse_int<N>(&self) -> syn::Result<N>
40  where
41    N: FromStr,
42    N::Err: Display,
43  {
44    if let Expr::Lit(expr_lit) = self && let Lit::Int(value) = &expr_lit.lit {
45      Ok(value.base10_parse::<N>()?)
46    } else {
47      Err(error!(self, "Expected an integer literal"))
48    }
49  }
50
51  fn parse_closure(&self) -> syn::Result<&ExprClosure> {
52    if let Expr::Closure(closure) = self {
53      Ok(closure)
54    } else {
55      Err(error!(self, "Expected a closure"))
56    }
57  }
58
59  fn parse_call_or_closure(self) -> syn::Result<CallOrClosure> {
60    match self {
61      Expr::Closure(closure) => Ok(CallOrClosure::Closure(closure)),
62      Expr::Call(call) => Ok(CallOrClosure::Call(call)),
63      _ => Err(error!(self, "Expected a path or a closure")),
64    }
65  }
66}
syn_utils/expr_trait.rs

syn_utils/
expr_trait.rs
