to_arithmetic
Functions that will convert a text representation of an arithmetic type to a value.
Converts from binary, octal, decimal and hex integrals, and decimal floating point types.
Supports conversion from char, wchar_t, char16_t and char32_t strings.
The numeric strings must not contain leading or trailing non-numeric characters. It is the responsibility of the user to
select the valid character range.
Integral types may be constexpr.
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to_arithmetic_status
An ETL enum type that defines the following enumeration values.
The are the values that may be set as the error code in to_arithmetic_result.
Valid
Invalid_Radix
Invalid_Format
Invalid_Float
Signed_To_Unsigned
Overflow
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to_arithmetic_result
The result type returned from etl::to_arithmetic.
template <typename TValue>
to_arithmetic_result
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Types
value_type TValue
error_type etl::to_arithmetic_status
unexpected_type etl::unexpected<etl::to_arithmetic_status>
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ETL_CONSTEXPR14
to_arithmetic_result()
Default constructor.
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ETL_CONSTEXPR14
to_arithmetic_result(const to_arithmetic_result& other)
Copy constructor.
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ETL_NODISCARD
ETL_CONSTEXPR14
bool has_value() const
Returns true if the result has a valid value.
If false then the value is undefined.
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ETL_NODISCARD
ETL_CONSTEXPR14
operator bool() const
Returns true if the result has a valid value.
If false then the value is undefined.
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ETL_NODISCARD
ETL_CONSTEXPR14
value_type value() const
Returns the value, if valid.
Otherwise undefined.
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ETL_NODISCARD
ETL_CONSTEXPR14
operator value_type() const
Returns the value, if valid.
Otherwise undefined.
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ETL_NODISCARD
ETL_CONSTEXPR14
error_type error() const
Returns the conversion status.
One of the following:-
Valid
Invalid_Radix
Invalid_Format
Invalid_Float
Signed_To_Unsigned
Overflow
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ETL_CONSTEXPR14
to_arithmetic_result& operator =(value_type value)
Assign from a value_type.
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ETL_CONSTEXPR14
to_arithmetic_result& operator =(unexpected_type status)
Assign from an unexpected_type.
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to_arithmetic
Convert a string to an integral or floating point value.
Supports:
etl::string_view (etl::basic_string_view<TChar>)
const pointer (to char, wchar_t, char16_t, char32_t) + length
etl::string, etl::wstring, etl::u16string or etl::u32string
template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const etl::basic_string_view<TChar>& view)
Text to integral or floating point from view and default decimal radix.
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template <typename TValue, typename TChar>
template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(etl::basic_string_view<TChar> view,
const etl::radix::value_type radix)
Text to integral from view and radix value type.
radix may be one of the following:-
etl::radix::binary
etl::radix::octal
etl::radix::decimal
etl::radix::hex
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ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const etl::basic_string_view<TChar>& view,
const etl::private_basic_format_spec::base_spec& spec)
Text to integral from view and radix format spec.
spec may be one of the following:-
etl::bin
etl::oct
etl::dec
etl::hex
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const TChar* cp,
size_t length)
Text to integral or floating point from pointer, length and default decimal radix.
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const TChar* cp,
size_t length,
const etl::radix::value_type radix)
Text to integral from pointer, length and radix value type.
radix may be one of the following:-
etl::radix::binary
etl::radix::octal
etl::radix::decimal
etl::radix::hex
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const TChar* cp,
size_t length,
const etl::private_basic_format_spec::base_spec& spec)
Text to integral from pointer, length and radix format spec.
spec may be one of the following:-
etl::bin
etl::oct
etl::dec
etl::hex
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const etl::ibasic_string<TChar>& str)
Text to integral or floating point from string and default decimal radix.
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const etl::ibasic_string<TChar>& str,
const etl::radix::value_type radix)
Text to integral from string and radix value type.
radix may be one of the following:-
etl::radix::binary
etl::radix::octal
etl::radix::decimal
etl::radix::hex
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template <typename TValue, typename TChar>
ETL_NODISCARD
ETL_CONSTEXPR14
etl::to_arithmetic_result<TValue> to_arithmetic(const etl::ibasic_string<TChar>& str,
const etl::private_basic_format_spec::base_spec& spec)
Text to integral from string and radix format spec.
spec may be one of the following:-
etl::bin
etl::oct
etl::dec
etl::hex
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Non-member functions
template <typename T>
ETL_CONSTEXPR14 bool operator ==(const etl::to_arithmetic_result<T>& lhs,
const etl::to_arithmetic_result<T>& rhs)
Equality test for etl::to_arithmetic_result
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template <typename T, typename U>
ETL_CONSTEXPR14 bool operator ==(const etl::to_arithmetic_result<T>& lhs,
const U& rhs)
Equality test for etl::to_arithmetic_result
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template <typename T, typename U>
ETL_CONSTEXPR14 bool operator ==(const T& lhs,
const etl::to_arithmetic_result<U>& rhs)
Equality test for etl::to_arithmetic_result
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template <typename T>
ETL_CONSTEXPR14 bool operator !=(const etl::to_arithmetic_result<T>& lhs,
const etl::to_arithmetic_result<T>& rhs)
Inequality test for etl::to_arithmetic_result
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template <typename T, typename U>
ETL_CONSTEXPR14 bool operator !=(const etl::to_arithmetic_result<T>& lhs,
const U& rhs)
Inequality test for etl::to_arithmetic_result
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template <typename T, typename U>
ETL_CONSTEXPR14 bool operator !=(const T& lhs,
const etl::to_arithmetic_result<T>& rhs)
Inequality test for etl::to_arithmetic_result
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Examples
Valid conversions
const char* BinaryText("1010011");
const etl::string<3> OctalText("123");
const etl::string<4> DecimalText(" 83 ");
const etl::string<2> HexText("85");
const etl::string<2> FloatText("-123e5");
int v1 = etl::to_arithmetic<int>(BinaryText, strlen(BinaryText), etl::bin);
int v2 = etl::to_arithmetic<int>(OctalText.c_str(), OctalText.size(), etl::radix::octal);
etl::string_view view(DecimalText.data() + 1, DecimalText.data() + 3);
int v3 = etl::to_arithmetic<int>(view);
int v4 = etl::to_arithmetic<int>(HexText, 16);
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Invalid conversions
const etl::string<10> Text1("abcd");
const etl::string<10> Text2(" 83 ");
const etl::string<10> Text3("-83");
const etl::string<10> Text4("4294967296");
const etl::string<10> Text5("1.23E10000");
etl::to_arithmetic_result result;
result = etl::to_arithmetic<int32_t>(Text1, 5);
result = etl::to_arithmetic<int32_t>(Text1);
result = etl::to_arithmetic<int32_t>(Text2);
result = etl::to_arithmetic<uint32_t>(Text3);
result = etl::to_arithmetic<int32_t>(Text4);
result = etl::to_arithmetic<float>(Text5);