Source file

Source file manager More...

Data Types
type	mod_source_file::t_source_file_container
	Source file container. More...

Functions/Subroutines
subroutine	mod_source_file::source_file_initialize (source_file, filename)
	Initialize the t_source_file_container from a file.
subroutine	mod_source_file::source_file_initialize_from_string (source_file, string, label)
	Initialize the t_source_file_container from a string.
character function	mod_source_file::source_file_read_character (source_file)
	Read the next character of the source file.
subroutine	mod_source_file::source_file_unread_character (source_file)
	Return to the previous position in the source file.
subroutine	mod_source_file::source_file_finalize (source_file)
	Close a source file.

Detailed Description

Source file manager

Brief description

The source file manager aims to record the current position of the read cursor and provide a way to set an arbitrary position to the read cursor.

Let us recall the lexer/parser organization with the 3 main units:

!!                                keyword list
!!                                      v
!!        ┏━━━━━━━━━━┓            ┌───────────┐          ┌────────────┐
!! files  ┃          ┃ characters │           │  tokens  │            │ ───────>
!! ─────> ┃   File   ┃ ──────────>│   Lexer   │ ───────> │   Parser   │  tokens / actions
!!        ┃          ┃            │           │          │            │ <───────
!!        ┗━━━━━━━━━━┛            └───────────┘          └────────────┘
!!       mod_source_file            mod_lexer             mod_parser
!!                                                        mod_identifier
!!                                                        mod_scope
!! 

Usage

As an example, consider a file notus.txt with the following content:

I
love
 
Notus <3

The following code opens the file and write every character preceded by the position, line and column number until the EOF is reached. It also diplays the newline flag.

type(t_source_file_container) :: source_file
character :: c
 
# Open notus.txt
call source_file_initialize(source_file, )
 
# Write header
write(*,'()')
 
# Make a loop until EOF is reached
do while (.not. source_file%eof)
   # Read the next character
   c = source_file_read_character(source_file)
 
   # Display the character and the source file container information
   write(*,'(i2.2,,i2.2,,i2.2,,l1,,a)') source_file%pos, source_file%line, source_file%column, source_file%newline, c
end do
 
write(*,'()')

Expected output:

P  R  C  NL character
01 01 01 F  I
02 01 02 T
 
03 02 01 F  l
04 02 02 F  o
05 02 03 F  v
06 02 04 F  e
07 02 05 T
 
08 03 01 T
 
09 04 01 F  N
10 04 02 F  o
11 04 03 F  t
12 04 04 F  u
13 04 05 F  s
14 04 06 F
15 04 07 F  <
16 04 08 F  3
EOF

Function/Subroutine Documentation

source_file_finalize()

subroutine mod_source_file::source_file_finalize

(

type(t_source_file_container), intent(inout)

source_file

)

Close a source file.

Deallocate arrays but do not reset flags. They are required for the read/unread routines.

Parameters

[in,out]

source_file

Source file container

source_file_initialize()

subroutine mod_source_file::source_file_initialize	(	type(t_source_file_container), intent(out)	source_file,
		character(len=*), intent(in)	filename )

Initialize the t_source_file_container from a file.

Rank 0 processor reads the source file and spread its content to all processors.

Parameters

[out]	source_file	Source file container
[in]	filename	Source file name

source_file_initialize_from_string()

subroutine mod_source_file::source_file_initialize_from_string	(	type(t_source_file_container), intent(out)	source_file,
		character(len=*), intent(in)	string,
		character(len=*), intent(in)	label )

Initialize the t_source_file_container from a string.

Rank 0 processor spreads its content to all processors.

Parameters

[out]	source_file	Source file container
[in]	string	String character
[in]	label	Label for the string

source_file_read_character()

character function mod_source_file::source_file_read_character

(

type(t_source_file_container), intent(inout)

source_file

)

Read the next character of the source file.

Behavior:

• Return only printable characters.
• If newline character is reached, return '\n' and set newline flag to .true..
• If end of file (EOF) is reached, return empty character and set eof flag to .true..
• Carriage return character '\r' is forbidden

Parameters

[in,out]

source_file

Source file container

Returns

c: next character in the file.

source_file_unread_character()

subroutine mod_source_file::source_file_unread_character

(

type(t_source_file_container), intent(inout)

source_file

)

Return to the previous position in the source file.

Parameters

[in,out]

source_file

Source file container