src/librustc_const_math/err.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 use syntax::ast;
  12
  13 #[derive(Debug, PartialEq, Eq, Clone)]
  14 pub enum ConstMathErr {
  15     NotInRange,
  16     CmpBetweenUnequalTypes,
  17     UnequalTypes(Op),
  18     Overflow(Op),
  19     ShiftNegative,
  20     DivisionByZero,
  21     RemainderByZero,
  22     UnsignedNegation,
  23     ULitOutOfRange(ast::UintTy),
  24     LitOutOfRange(ast::IntTy),
  25 }
  26 pub use self::ConstMathErr::*;
  27
  28 #[derive(Debug, PartialEq, Eq, Clone)]
  29 pub enum Op {
  30     Add,
  31     Sub,
  32     Mul,
  33     Div,
  34     Rem,
  35     Shr,
  36     Shl,
  37     Neg,
  38     BitAnd,
  39     BitOr,
  40     BitXor,
  41 }
  42
  43 impl ConstMathErr {
  44     pub fn description(&self) -> &'static str {
  45         use self::Op::*;
  46         match *self {
  47             NotInRange => "inferred value out of range",
  48             CmpBetweenUnequalTypes => "compared two integrals of different types",
  49             UnequalTypes(Add) => "tried to add two integrals of different types",
  50             UnequalTypes(Sub) => "tried to subtract two integrals of different types",
  51             UnequalTypes(Mul) => "tried to multiply two integrals of different types",
  52             UnequalTypes(Div) => "tried to divide two integrals of different types",
  53             UnequalTypes(Rem) => {
  54                 "tried to calculate the remainder of two integrals of different types"
  55             },
  56             UnequalTypes(BitAnd) => "tried to bitand two integrals of different types",
  57             UnequalTypes(BitOr) => "tried to bitor two integrals of different types",
  58             UnequalTypes(BitXor) => "tried to xor two integrals of different types",
  59             UnequalTypes(_) => unreachable!(),
  60             Overflow(Add) => "attempted to add with overflow",
  61             Overflow(Sub) => "attempted to subtract with overflow",
  62             Overflow(Mul) => "attempted to multiply with overflow",
  63             Overflow(Div) => "attempted to divide with overflow",
  64             Overflow(Rem) => "attempted to calculate the remainder with overflow",
  65             Overflow(Neg) => "attempted to negate with overflow",
  66             Overflow(Shr) => "attempted to shift right with overflow",
  67             Overflow(Shl) => "attempted to shift left with overflow",
  68             Overflow(_) => unreachable!(),
  69             ShiftNegative => "attempted to shift by a negative amount",
  70             DivisionByZero => "attempted to divide by zero",
  71             RemainderByZero => "attempted to calculate the remainder with a divisor of zero",
  72             UnsignedNegation => "unary negation of unsigned integer",
  73             ULitOutOfRange(ast::UintTy::U8) => "literal out of range for u8",
  74             ULitOutOfRange(ast::UintTy::U16) => "literal out of range for u16",
  75             ULitOutOfRange(ast::UintTy::U32) => "literal out of range for u32",
  76             ULitOutOfRange(ast::UintTy::U64) => "literal out of range for u64",
  77             ULitOutOfRange(ast::UintTy::Us) => "literal out of range for usize",
  78             LitOutOfRange(ast::IntTy::I8) => "literal out of range for i8",
  79             LitOutOfRange(ast::IntTy::I16) => "literal out of range for i16",
  80             LitOutOfRange(ast::IntTy::I32) => "literal out of range for i32",
  81             LitOutOfRange(ast::IntTy::I64) => "literal out of range for i64",
  82             LitOutOfRange(ast::IntTy::Is) => "literal out of range for isize",
  83         }
  84     }
  85 }