Aleph::CsvReader Class Reference

Lazy CSV reader for large files. More...

#include <parse-csv.H>

Collaboration diagram for Aleph::CsvReader:

Classes
class	Iterator

Public Member Functions
	CsvReader (const std::string &filename, char delimiter=',')
	Construct reader from file path.
	CsvReader (std::istream &stream, char delimiter=',')
	Construct reader from stream.
Array< std::string >	read_header ()
	Read and store the header row.
bool	has_next () const
	Check if more rows are available.
Array< std::string >	next ()
	Read the next row as Array.
CsvRow	next_row ()
	Read the next row with header access.
size_t	rows_read () const
	Get number of rows read so far.
const Array< std::string > &	header () const
	Get the header (if read).
bool	has_header () const
	Check if header was read.
void	skip (size_t n)
	Skip N rows.
void	reset ()
	Reset to beginning (only works for file-based readers).
Iterator	begin ()
Iterator	end ()

Private Attributes
std::ifstream	file_
std::istream *	stream_
bool	owns_stream_
char	delimiter_
Array< std::string >	header_
bool	has_header_
size_t	row_count_

Detailed Description

Lazy CSV reader for large files.

CsvReader provides an iterator-based interface for reading CSV files row by row without loading the entire file into memory.

// Read large CSV file efficiently
CsvReader reader("large_file.csv");
 
// Skip header and use it for column names
reader.read_header();
 
while (reader.has_next())
{
  CsvRow row = reader.next_row();
  process(row["id"], row["value"]);
}
 
// Or use range-based for (without header)
CsvReader reader2("data.csv");
for (const auto & row : reader2)
  std::cout << row[0] << "\n";

Definition at line 710 of file parse-csv.H.

Constructor & Destructor Documentation

CsvReader() [1/2]

Aleph::CsvReader::CsvReader ( const std::string &  filename, char  delimiter = ','  )

inlineexplicit

Construct reader from file path.

Exceptions

std::runtime_error

If file cannot be opened.

Definition at line 723 of file parse-csv.H.

References file_, and Aleph::maps().

CsvReader() [2/2]

Aleph::CsvReader::CsvReader ( std::istream &  stream, char  delimiter = ','  )

inlineexplicit

Construct reader from stream.

Definition at line 732 of file parse-csv.H.

Member Function Documentation

begin()

Iterator Aleph::CsvReader::begin ( )

inline

Definition at line 831 of file parse-csv.H.

end()

Iterator Aleph::CsvReader::end ( )

inline

Definition at line 832 of file parse-csv.H.

has_header()

bool Aleph::CsvReader::has_header ( ) const

inline

Check if header was read.

Definition at line 775 of file parse-csv.H.

References has_header_.

has_next()

bool Aleph::CsvReader::has_next ( ) const

inline

Check if more rows are available.

Definition at line 746 of file parse-csv.H.

References Aleph::maps(), and stream_.

Referenced by Aleph::CsvReader::Iterator::Iterator(), Aleph::CsvReader::Iterator::operator++(), and skip().

header()

const Array< std::string > & Aleph::CsvReader::header ( ) const

inline

Get the header (if read).

Definition at line 772 of file parse-csv.H.

References header_.

next()

Array< std::string > Aleph::CsvReader::next ( )

inline

Read the next row as Array.

Definition at line 752 of file parse-csv.H.

References Aleph::csv_read_row(), delimiter_, row_count_, and stream_.

Referenced by Aleph::CsvReader::Iterator::Iterator(), Aleph::CsvReader::Iterator::operator++(), and skip().

next_row()

CsvRow Aleph::CsvReader::next_row ( )

inline

Read the next row with header access.

Definition at line 759 of file parse-csv.H.

References Aleph::csv_read_row(), delimiter_, has_header_, header_, row_count_, and stream_.

read_header()

Array< std::string > Aleph::CsvReader::read_header ( )

inline

Read and store the header row.

Returns

The header row.

Definition at line 738 of file parse-csv.H.

References Aleph::csv_read_row(), delimiter_, has_header_, header_, and stream_.

Referenced by reset().

reset()

void Aleph::CsvReader::reset ( )

inline

Reset to beginning (only works for file-based readers).

Definition at line 785 of file parse-csv.H.

References file_, has_header_, owns_stream_, read_header(), and row_count_.

rows_read()

size_t Aleph::CsvReader::rows_read ( ) const

inline

Get number of rows read so far.

Definition at line 769 of file parse-csv.H.

References row_count_.

skip()

void Aleph::CsvReader::skip ( size_t  n )

inline

Skip N rows.

Definition at line 778 of file parse-csv.H.

References has_next(), Aleph::maps(), and next().

Member Data Documentation

delimiter_

char Aleph::CsvReader::delimiter_

private

Definition at line 715 of file parse-csv.H.

Referenced by next(), next_row(), and read_header().

file_

std::ifstream Aleph::CsvReader::file_

private

Definition at line 712 of file parse-csv.H.

Referenced by CsvReader(), and reset().

has_header_

bool Aleph::CsvReader::has_header_

private

Definition at line 717 of file parse-csv.H.

Referenced by has_header(), next_row(), read_header(), and reset().

header_

Array<std::string> Aleph::CsvReader::header_

private

Definition at line 716 of file parse-csv.H.

Referenced by header(), next_row(), and read_header().

owns_stream_

bool Aleph::CsvReader::owns_stream_

private

Definition at line 714 of file parse-csv.H.

Referenced by reset().

row_count_

size_t Aleph::CsvReader::row_count_

private

Definition at line 718 of file parse-csv.H.

Referenced by next(), next_row(), reset(), and rows_read().

stream_

std::istream* Aleph::CsvReader::stream_

private

Definition at line 713 of file parse-csv.H.

Referenced by has_next(), next(), next_row(), and read_header().

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The documentation for this class was generated from the following file:

• parse-csv.H