41 lines
921 B
Rust
41 lines
921 B
Rust
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use crate::token::Tok;
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#[derive(Clone, Copy)]
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pub enum Mode {
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Module,
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Interactive,
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Expression,
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}
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impl Mode {
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pub(crate) fn to_marker(self) -> Tok {
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match self {
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Self::Module => Tok::StartModule,
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Self::Interactive => Tok::StartInteractive,
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Self::Expression => Tok::StartExpression,
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}
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}
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}
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impl std::str::FromStr for Mode {
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type Err = ModeParseError;
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fn from_str(s: &str) -> Result<Self, ModeParseError> {
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match s {
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"exec" | "single" => Ok(Mode::Module),
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"eval" => Ok(Mode::Expression),
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_ => Err(ModeParseError { _priv: () }),
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}
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}
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}
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#[derive(Debug)]
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pub struct ModeParseError {
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_priv: (),
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}
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impl std::fmt::Display for ModeParseError {
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fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
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write!(f, r#"mode should be "exec", "eval", or "single""#)
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}
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}
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