9.5.7 Line directives

9.5.7 Line directives

Line directives may be used to alter the line numbers and source file names

that are reported by the compiler in

output such as warnings and errors.

[Note: Line directives are most commonly used in meta-programming tools

that generate C# source code from

some other text input. end note]

pp-line::

whitespaceopt # whitespaceopt line whitespace line-indicator pp-new-line

line-indicator::

decimal-digits whitespace file-name

decimal-digits

default

file-name::

" file-name-characters "

file-name-characters::

file-name-character

file-name-characters file-name-character

file-name-character::

Any character except " (U+0022), and new-line

When no #line directives are present, the compiler reports true line

numbers and source file names in its output.

When processing a #line directive that includes a line-indicator that is

not default, the compiler treats the line

after the directive as having the given line number (and file name, if

specified).

A #line default directive reverses the effect of all preceding #line

directives. The compiler reports true line

information for subsequent lines, precisely as if no #line directives had

been processed.

[Note: Note that a file-name differs from a regular string literal in that

escape characters are not processed; the

.\. character simply designates an ordinary back-slash character within a

file-name. end note]