6.86. kink/program/LOCATION¶
6.86.1. type location¶
`location` is a position index of Unicode code points in a program text.
A `location` consists of the following attributes:
• Program: a `program`
• Pos: a position index as an integer `num`.
Invariant
0 <= Pos <= Program.text.size
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.program.repr) # => (program name="foo.kn")
stdout.print_line(Loc.line_num.repr) # => 2
stdout.print_line(Loc.col_num.repr) # => 5
stdout.print_line(Loc.line.repr) # => "foo(Bar)\n"
stdout.print_line(Loc.indicator.repr) # => "foo(-->Bar)"
stdout.print_line(Loc.desc.repr) # => "foo.kn L2 C5"
6.86.1.1. Loc.program¶
`program` returns `Program` attribute of `Loc`.
6.86.1.2. Loc.pos¶
`pos` returns `Pos` attribute of `Loc`.
6.86.1.3. Loc.line_num¶
`line_num` returns the line number of `Loc` as an integer `num`.
The line number is the number of LF characters plus one in the program text before `Loc`.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.line_num.repr) # => 2
6.86.1.4. Loc.col_num¶
`col_num` returns the column number of `Loc` as an integer `num`.
The result is the number of code points plus one in the line before `Loc`.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.col_num.repr) # => 5
6.86.1.5. Loc.line¶
`line` returns the line of `Loc` as a `str`.
`line` returns a slice of the program text in the range [From, To), where `From` is the code point index of the beginning of the line, and `To` is the code point index of the beginning of the next line or the end of the text. Thus, the result `str` may include an LF character as the last code point.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.line.repr) # => "foo(Bar)\n"
6.86.1.6. Loc.indicator¶
`indicator` returns a `str` which represents the position of `Loc` in the line.
The result `str` does not contain CR or LF characters.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.indicator.repr) # => "foo(-->Bar)"
6.86.1.7. Loc.desc¶
`desc` returns a `str` which describes the program name, the line number, and the column number.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.desc.repr) # => "foo.kn L2 C5"
6.86.1.8. Loc1 == Loc2¶
`==` operator, or `op_eq` method, returns whether two `location` values have the equal `Program` and `Pos` attributes.
6.86.1.9. Loc.repr¶
`repr` returns a `str` representation of `Loc` for debugging purposes.
Example
:LOCATION.require_from('kink/program/')
:PROGRAM.require_from('kink/program/')
:Program <- PROGRAM.new('foo.kn' "ping(Pong)\nfoo(Bar)\n")
:Loc <- LOCATION.new(Program 15)
stdout.print_line(Loc.repr) # => (location foo.kn L2 C5)
6.86.2. LOCATION.new(Program Pos)¶
`new` returns a `location` with the given attributes.
Preconditions
`Program` must be a `program`.
`Pos` must be an integer `num`.
0 <= Pos <= Program.text.size
6.86.3. LOCATION.empty¶
`empty` returns a `location` with the empty program name, the empty program text, and Pos=0.
6.86.4. LOCATION.is?(Val)¶
`is?` returns whether `Val` is a `location`.