diff options
| -rw-r--r-- | source/tanya/format/conv.d | 195 |
1 files changed, 179 insertions, 16 deletions
diff --git a/source/tanya/format/conv.d b/source/tanya/format/conv.d index e7c6b02..7a13178 100644 --- a/source/tanya/format/conv.d +++ b/source/tanya/format/conv.d @@ -38,7 +38,8 @@ final class ConvException : Exception /** * If the source type $(D_PARAM From) and the target type $(D_PARAM To) are - * equal, does nothing. + * equal, does nothing. If $(D_PARAM From) can be implicitly converted to + * $(D_PARAM To), just returns $(D_PARAM from). * * Params: * From = Source type. @@ -56,7 +57,7 @@ template to(To) } To to(From)(From from) - if (is(Unqual!To == Unqual!From)) + if (is(Unqual!To == Unqual!From) || isNumeric!From && isFloatingPoint!To) { return from; } @@ -78,9 +79,7 @@ private pure nothrow @safe @nogc unittest /** * Performs checked conversion from an integral type $(D_PARAM From) to an - * integral type $(D_PARAM To). If the conversion isn't possible (for example - * because $(D_PARAM from) is too small or too large to be represented by - * $(D_PARAM To)), an exception is thrown. + * integral type $(D_PARAM To). * * Params: * From = Source type. @@ -89,10 +88,14 @@ private pure nothrow @safe @nogc unittest * * Returns: $(D_PARAM from) converted to $(D_PARAM To). * - * Throws: $(D_PSYMBOL ConvException). + * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is too small or too + * large to be represented by $(D_PARAM To). */ To to(To, From)(From from) -if (isIntegral!From && isIntegral!To && !is(To == From)) +if (isIntegral!From + && isIntegral!To + && !is(Unqual!To == Unqual!From) + && !is(To == enum)) { static if ((isUnsigned!From && isSigned!To && From.sizeof == To.sizeof) || From.sizeof > To.sizeof) @@ -254,10 +257,19 @@ private unittest defaultAllocator.dispose(exception); } +private @nogc unittest +{ + enum Test : int + { + one, + two, + } + assert(Test.one.to!int == 0); + assert(Test.two.to!int == 1); +} + /** - * Converts a number to a boolean. If $(D_PARAM from) is greater than `1` or - * less than `0`, an exception is thrown, `0` results in $(D_KEYWORD false) and - * all other values result in $(D_KEYWORD true). + * Converts a number to a boolean. * * Params: * From = Source type. @@ -267,10 +279,11 @@ private unittest * Returns: $(D_KEYWORD true) if $(D_INLINECODE from > 0 && from <= 1), * otherwise $(D_KEYWORD false). * - * Throws: $(D_PSYMBOL ConvException). + * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is greater than `1` or + * less than `0`. */ To to(To, From)(From from) -if (isNumeric!From && is(Unqual!To == bool) && !is(To == From)) +if (isNumeric!From && is(Unqual!To == bool) && !is(Unqual!To == Unqual!From)) { if (from == 0) { @@ -289,7 +302,7 @@ if (isNumeric!From && is(Unqual!To == bool) && !is(To == From)) "Positive number overflow"); } -private unittest +private @nogc unittest { assert(0.0.to!bool == false); assert(0.2.to!bool == true); @@ -300,7 +313,7 @@ private unittest assert(1.to!bool == true); } -private unittest +private @nogc unittest { ConvException exception; try @@ -315,7 +328,7 @@ private unittest defaultAllocator.dispose(exception); } -private unittest +private @nogc unittest { ConvException exception; try @@ -342,7 +355,7 @@ private unittest * Returns: `1` if $(D_PARAM from) is $(D_KEYWORD true), otherwise `0`. */ To to(To, From)(From from) -if (is(Unqual!From == bool) && isNumeric!To && !is(To == From)) +if (is(Unqual!From == bool) && isNumeric!To && !is(Unqual!To == Unqual!From)) { return from; } @@ -368,3 +381,153 @@ pure nothrow @safe @nogc unittest assert(false.to!uint == 0); assert(false.to!int == 0); } + +/** + * Converts a floating point number to an integral type. + * + * Params: + * From = Source type. + * To = Target type. + * from = Source value. + * + * Returns: Truncated $(D_PARAM from) (everything after the decimal point is + * dropped. + * + * Throws: $(D_PSYMBOL ConvException) if + * $(D_INLINECODE from < To.min || from > To.max). + */ +To to(To, From)(From from) +if (isFloatingPoint!From + && isIntegral!To + && !is(Unqual!To == Unqual!From) + && !is(To == enum)) +{ + if (from > To.max) + { + throw make!ConvException(defaultAllocator, + "Positive number overflow"); + } + else if (from < To.min) + { + throw make!ConvException(defaultAllocator, + "Negative number overflow"); + } + return cast(To) from; +} + +/// +@nogc unittest +{ + assert(1.5.to!int == 1); + assert(2147483646.5.to!int == 2147483646); + assert((-2147483647.5).to!int == -2147483647); + assert(2147483646.5.to!uint == 2147483646); +} + +private @nogc unittest +{ + ConvException exception; + try + { + assert(2147483647.5.to!int == 2147483647); + } + catch (ConvException e) + { + exception = e; + } + assert(exception !is null); + defaultAllocator.dispose(exception); +} + +private @nogc unittest +{ + ConvException exception; + try + { + assert((-2147483648.5).to!int == -2147483648); + } + catch (ConvException e) + { + exception = e; + } + assert(exception !is null); + defaultAllocator.dispose(exception); +} + +private @nogc unittest +{ + ConvException exception; + try + { + assert((-21474.5).to!uint == -21474); + } + catch (ConvException e) + { + exception = e; + } + assert(exception !is null); + defaultAllocator.dispose(exception); +} + +/** + * Performs checked conversion from an integral type $(D_PARAM From) to an + * $(D_KEYWORD enum). + * + * Params: + * From = Source type. + * To = Target type. + * from = Source value. + * + * Returns: $(D_KEYWORD enum) value. + * + * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is not a member of + * $(D_PSYMBOL To). + + */ +To to(To, From)(From from) +if (isIntegral!From && is(To == enum)) +{ + foreach (m; EnumMembers!To) + { + if (from == m) + { + return m; + } + } + throw make!ConvException(defaultAllocator, + "Value not found in enum '" ~ To.stringof ~ "'"); +} + +/// +@nogc unittest +{ + enum Test : int + { + one, + two, + } + static assert(is(typeof(1.to!Test) == Test)); + assert(0.to!Test == Test.one); + assert(1.to!Test == Test.two); +} + +private @nogc unittest +{ + enum Test : uint + { + one, + two, + } + + ConvException exception; + try + { + assert(5.to!Test == Test.one); + } + catch (ConvException e) + { + exception = e; + } + assert(exception !is null); + defaultAllocator.dispose(exception); +} |