A C++ template library for embedded applications
MIT licensed
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Designed and
maintained by
John Wellbelove
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string_stream

wstring_stream

u16string_stream

u32string_stream


Classes to build strings using a streaming api.
Uses etl::basic_format_spec to define the required formatting.

The documentation below is for etl::string_stream.
The other streams have a similar API, though using w, u16 or u32 types.
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Member functions
explicit string_stream(etl::istring& str)
Construct, using the supplied string as a buffer.
Uses the default format spec.
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string_stream(etl::istring& str, const etl::format_spec& spec)
Construct, using the supplied string as a buffer.
Initialised with the supplied format spec.
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void set_format(const etl::format_spec& spec_)
Sets a new format spec to use.
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const etl::format_spec& get_format() const
Gets the current format spec.
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etl::istring& str()
Gets a reference to the internal string.
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const etl::istring& str() const
Gets a const reference to the internal string.
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void str(const etl::istring::const_pointer p)
Resets the internal string to the text pointed to by p.
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void str(const etl::istring& text)
Resets the internal string to text.
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Streaming operators

string_stream& operator <<(string_stream& ss, T value)

Where T may be one of the following:-

Any fundamental type.
etl::format_spec
etl::setbase(n)
etl::bin
etl::oct
etl::dec
etl::hex
etl::setfill(c)
etl::setw(n)
etl::setprecision(n)
etl::left
etl::right
etl::boolalpha
etl::noboolalpha
etl::uppercase
etl::nouppercase
etl::showbase
etl::noshowbase
etl::string
etl::istring
etl::string_view
const char*
See etl::format_spec

Custom user types may be streamed by overloading the streaming operator.
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Examples

Using format_spec
etl::format_spec  format1 = etl::format_spec().hex().width(8).fill('0');
etl::format_spec  format2 = etl::format_spec().width(6).fill('#').precision(3);
etl::string<50>    text;
etl::string_stream stream(text);

stream << format1 << 1193046 << " " << format2 << 3.1415;
const etl::istring& result = stream.str();

text is set to "00123456 #3.142"
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Using stream manipulators
etl::string<50>    text;
etl::string_stream stream(text);

stream << etl::hex << etl::setw(8) << etl::setfill('0') << 1193046
       << " "
       << etl::setw(6) << etl::setfill('#') << etl::setprecision(3) << 3.1415;
const etl::istring& result = stream.str();

text is set to "00123456 #3.142"
string_stream.h, wstring_stream.h,
u16string_stream.h, u32string_stream.h