# Read a string until the end of the line.
#
- # The line terminator '\n', if any, is preserved in each line.
- # Use the method `Text::chomp` to safely remove it.
+ # The line terminator '\n' and '\r\n', if any, is removed in each line.
#
# ~~~
# var txt = "Hello\n\nWorld\n"
# var i = new StringIStream(txt)
- # assert i.read_line == "Hello\n"
- # assert i.read_line == "\n"
- # assert i.read_line == "World\n"
+ # assert i.read_line == "Hello"
+ # assert i.read_line == ""
+ # assert i.read_line == "World"
# assert i.eof
# ~~~
#
- # If `\n` is not present at the end of the result, it means that
- # a non-eol terminated last line was returned.
+ # Only LINE FEED (`\n`), CARRIAGE RETURN & LINE FEED (`\r\n`), and
+ # the end or file (EOF) is considered to delimit the end of lines.
+ # CARRIAGE RETURN (`\r`) alone is not used for the end of line.
#
# ~~~
- # var i2 = new StringIStream("hello")
- # assert not i2.eof
- # assert i2.read_line == "hello"
+ # var txt2 = "Hello\r\n\n\rWorld"
+ # var i2 = new StringIStream(txt2)
+ # assert i2.read_line == "Hello"
+ # assert i2.read_line == ""
+ # assert i2.read_line == "\rWorld"
# assert i2.eof
# ~~~
#
- # NOTE: Only LINE FEED (`\n`) is considered to delimit the end of lines.
+ # NOTE: Use `append_line_to` if the line terminator needs to be preserved.
fun read_line: String
do
if last_error != null then return ""
- assert not eof
+ if eof then return ""
var s = new FlatBuffer
append_line_to(s)
- return s.to_s
+ return s.to_s.chomp
end
# Read all the lines until the eof.
#
- # The line terminator '\n' is removed in each line,
+ # The line terminator '\n' and `\r\n` is removed in each line,
#
# ~~~
# var txt = "Hello\n\nWorld\n"
# This method is more efficient that splitting
# the result of `read_all`.
#
- # NOTE: Only LINE FEED (`\n`) is considered to delimit the end of lines.
+ # NOTE: SEE `read_line` for details.
fun read_lines: Array[String]
do
var res = new Array[String]
while not eof do
- res.add read_line.chomp
+ res.add read_line
end
return res
end
# Read all the stream until the eof.
+ #
+ # The content of the file is returned verbatim.
+ #
+ # ~~~
+ # var txt = "Hello\n\nWorld\n"
+ # var i = new StringIStream(txt)
+ # assert i.read_all == txt
+ # ~~~
fun read_all: String
do
if last_error != null then return ""
# Read a string until the end of the line and append it to `s`.
#
- # SEE: `read_line` for details.
+ # Unlike `read_line` and other related methods,
+ # the line terminator '\n', if any, is preserved in each line.
+ # Use the method `Text::chomp` to safely remove it.
+ #
+ # ~~~
+ # var txt = "Hello\n\nWorld\n"
+ # var i = new StringIStream(txt)
+ # var b = new FlatBuffer
+ # i.append_line_to(b)
+ # assert b == "Hello\n"
+ # i.append_line_to(b)
+ # assert b == "Hello\n\n"
+ # i.append_line_to(b)
+ # assert b == txt
+ # assert i.eof
+ # ~~~
+ #
+ # If `\n` is not present at the end of the result, it means that
+ # a non-eol terminated last line was returned.
+ #
+ # ~~~
+ # var i2 = new StringIStream("hello")
+ # assert not i2.eof
+ # var b2 = new FlatBuffer
+ # i2.append_line_to(b2)
+ # assert b2 == "hello"
+ # assert i2.eof
+ # ~~~
+ #
+ # NOTE: The single character LINE FEED (`\n`) delimits the end of lines.
+ # Therefore CARRIAGE RETURN & LINE FEED (`\r\n`) is also recognized.
fun append_line_to(s: Buffer)
do
if last_error != null then return
super IStream
redef fun read_char
do
- if last_error != null then return 0
- if eof then last_error = new IOError("Stream has reached eof")
- if _buffer_pos >= _buffer.length then
- fill_buffer
- end
- if _buffer_pos >= _buffer.length then
+ if last_error != null then return -1
+ if eof then
+ last_error = new IOError("Stream has reached eof")
return -1
end
var c = _buffer.chars[_buffer_pos]
if last_error != null then return ""
if _buffer.length == _buffer_pos then
if not eof then
- fill_buffer
return read(i)
end
return ""
var i = _buffer_pos
while i < _buffer.length and _buffer.chars[i] != '\n' do i += 1
+ var eol
+ if i < _buffer.length then
+ assert _buffer.chars[i] == '\n'
+ i += 1
+ eol = true
+ else
+ eol = false
+ end
+
# if there is something to append
if i > _buffer_pos then
# Enlarge the string (if needed)
s.add(_buffer.chars[j])
j += 1
end
+ _buffer_pos = i
+ else
+ assert end_reached
+ return
end
- if i < _buffer.length then
- # so \n is in _buffer[i]
- _buffer_pos = i + 1 # skip \n
+ if eol then
+ # so \n is found
return
else
# so \n is not found
- _buffer_pos = i
- if end_reached then
- return
- else
- fill_buffer
- end
+ if end_reached then return
+ fill_buffer
end
end
end
- redef fun eof do return _buffer_pos >= _buffer.length and end_reached
+ redef fun eof
+ do
+ if _buffer_pos < _buffer.length then return false
+ if end_reached then return true
+ fill_buffer
+ return _buffer_pos >= _buffer.length and end_reached
+ end
# The buffer
private var buffer: nullable FlatBuffer = null
# assert "\na\nb\tc\t".trim == "a\nb\tc"
fun trim: SELFTYPE do return (self.l_trim).r_trim
- # Returns `self` removed from its last `\n` (if any).
+ # Returns `self` removed from its last line terminator (if any).
#
# assert "Hello\n".chomp == "Hello"
# assert "Hello".chomp == "Hello"
- # assert "\n\n\n".chomp == "\n\n"
#
- # This method is mainly used to remove the LINE_FEED character from lines of text.
+ # assert "\n".chomp == ""
+ # assert "".chomp == ""
+ #
+ # Line terminators are `"\n"`, `"\r\n"` and `"\r"`.
+ # A single line terminator, the last one, is removed.
+ #
+ # assert "\r\n".chomp == ""
+ # assert "\r\n\n".chomp == "\r\n"
+ # assert "\r\n\r\n".chomp == "\r\n"
+ # assert "\r\n\r".chomp == "\r\n"
+ #
+ # Note: unlike with most IO methods like `IStream::read_line`,
+ # a single `\r` is considered here to be a line terminator and will be removed.
fun chomp: SELFTYPE
do
- if self.is_empty or self.chars.last != '\n' then return self
- return substring(0, length-1)
+ var len = length
+ if len == 0 then return self
+ var l = self.chars.last
+ if l == '\r' then
+ return substring(0, len-1)
+ else if l != '\n' then
+ return self
+ else if len > 1 and self.chars[len-2] == '\r' then
+ return substring(0, len-2)
+ else
+ return substring(0, len-1)
+ end
end
# Justify a self in a space of `length`
nitlanguage / nit.git / commitdiff