#include <cstring>
namespace llvm {
-
+
/// \brief A switch()-like statement whose cases are string literals.
///
/// The StringSwitch class is a simple form of a switch() statement that
/// .Case("green", Green)
/// .Case("blue", Blue)
/// .Case("indigo", Indigo)
-/// .Case("violet", Violet)
+/// .Cases("violet", "purple", Violet)
/// .Default(UnknownColor);
/// \endcode
template<typename T>
class StringSwitch {
/// \brief The string we are matching.
StringRef Str;
-
+
/// \brief The result of this switch statement, once known.
T Result;
-
+
/// \brief Set true when the result of this switch is already known; in this
/// case, Result is valid.
bool ResultKnown;
-
+
public:
- explicit StringSwitch(StringRef Str)
+ explicit StringSwitch(StringRef Str)
: Str(Str), ResultKnown(false) { }
-
+
template<unsigned N>
StringSwitch& Case(const char (&S)[N], const T& Value) {
- if (!ResultKnown && N-1 == Str.size() &&
+ if (!ResultKnown && N-1 == Str.size() &&
(std::memcmp(S, Str.data(), N-1) == 0)) {
Result = Value;
ResultKnown = true;
}
-
+
return *this;
}
-
+
template<unsigned N0, unsigned N1>
StringSwitch& Cases(const char (&S0)[N0], const char (&S1)[N1],
const T& Value) {
return Case(S0, Value).Case(S1, Value);
}
-
+
template<unsigned N0, unsigned N1, unsigned N2>
StringSwitch& Cases(const char (&S0)[N0], const char (&S1)[N1],
const char (&S2)[N2], const T& Value) {
return Case(S0, Value).Case(S1, Value).Case(S2, Value);
}
-
+
template<unsigned N0, unsigned N1, unsigned N2, unsigned N3>
StringSwitch& Cases(const char (&S0)[N0], const char (&S1)[N1],
const char (&S2)[N2], const char (&S3)[N3],
template<unsigned N0, unsigned N1, unsigned N2, unsigned N3, unsigned N4>
StringSwitch& Cases(const char (&S0)[N0], const char (&S1)[N1],
const char (&S2)[N2], const char (&S3)[N3],
- const char (&S4)[N4], const T& Value) {
+ const char (&S4)[N4], const T& Value) {
return Case(S0, Value).Case(S1, Value).Case(S2, Value).Case(S3, Value)
.Case(S4, Value);
}
-
+
T Default(const T& Value) {
if (ResultKnown)
return Result;
-
+
return Value;
}
-
+
operator T() {
assert(ResultKnown && "Fell off the end of a string-switch");
return Result;