pub struct Writer { /* private fields */ }
Expand description
A writer for CSV data.
§RFC 4180
This writer conforms to RFC 4180 with one exception: it doesn’t guarantee that all records written are of the same length. Instead, the onus is on the caller to ensure that all records written are of the same length.
Note that the default configuration of a Writer
uses \n
for record
terminators instead of \r\n
as specified by RFC 4180. Use the
terminator
method on WriterBuilder
to set the terminator to \r\n
if
it’s desired.
Implementations§
source§impl Writer
impl Writer
sourcepub fn finish(&mut self, output: &mut [u8]) -> (WriteResult, usize)
pub fn finish(&mut self, output: &mut [u8]) -> (WriteResult, usize)
Finish writing CSV data to output
.
This must be called when one is done writing CSV data to output
.
In particular, it will write closing quotes if necessary.
sourcepub fn field(
&mut self,
input: &[u8],
output: &mut [u8]
) -> (WriteResult, usize, usize)
pub fn field( &mut self, input: &[u8], output: &mut [u8] ) -> (WriteResult, usize, usize)
Write a single CSV field from input
to output
while employing this
writer’s quoting style.
This returns the result of writing field data, in addition to the
number of bytes consumed from input
and the number of bytes
written to output
.
The result of writing field data is either WriteResult::InputEmpty
or WriteResult::OutputFull
. The former occurs when all bytes in
input
were copied to output
, while the latter occurs when output
is too small to fit everything from input
. The maximum number of
bytes that can be written to output
is 2 + (2 * input.len())
because of quoting. (The worst case is a field consisting entirely
of quotes.)
Multiple successive calls to field
will write more data to the same
field. Subsequent fields can be written by calling either delimiter
or terminator
first.
If this writer’s quoting style is QuoteStyle::Necessary
, then input
should contain the entire field. Otherwise, whether the field needs
to be quoted or not cannot be determined.
sourcepub fn delimiter(&mut self, output: &mut [u8]) -> (WriteResult, usize)
pub fn delimiter(&mut self, output: &mut [u8]) -> (WriteResult, usize)
Write the configured field delimiter to output
.
If the output buffer does not have enough room to fit
a field delimiter, then nothing is written to output
and WriteResult::OutputFull
is returned. Otherwise,
WriteResult::InputEmpty
is returned along with the number of bytes
written to output
(which is 1
in case of an unquoted
field, or 2
in case of an end quote and a field separator).
sourcepub fn terminator(&mut self, output: &mut [u8]) -> (WriteResult, usize)
pub fn terminator(&mut self, output: &mut [u8]) -> (WriteResult, usize)
Write the configured record terminator to output
.
If the output buffer does not have enough room to fit a record
terminator, then no part of the terminator is written and
WriteResult::OutputFull
is returned. Otherwise,
WriteResult::InputEmpty
is returned along with the number of bytes
written to output
(which is always 1
or 2
).
sourcepub fn is_special_byte(&self, b: u8) -> bool
pub fn is_special_byte(&self, b: u8) -> bool
Returns true if and only if the given byte corresponds to a special byte in this CSV writer’s configuration.
Note that this does not take into account this writer’s quoting style.
sourcepub fn should_quote(&self, input: &[u8]) -> bool
pub fn should_quote(&self, input: &[u8]) -> bool
Returns true if and only if we should put the given field data in quotes. This takes the quoting style into account.
sourcepub fn get_delimiter(&self) -> u8
pub fn get_delimiter(&self) -> u8
Return the delimiter used for this writer.
sourcepub fn get_terminator(&self) -> Terminator
pub fn get_terminator(&self) -> Terminator
Return the terminator used for this writer.
sourcepub fn get_quote_style(&self) -> QuoteStyle
pub fn get_quote_style(&self) -> QuoteStyle
Return the quoting style used for this writer.
sourcepub fn get_escape(&self) -> u8
pub fn get_escape(&self) -> u8
Return the escape character used for this writer.
sourcepub fn get_double_quote(&self) -> bool
pub fn get_double_quote(&self) -> bool
Return whether this writer doubles quotes or not. When the writer does not double quotes, it will escape them using the escape character.