Logging

Definition

Global logging and verbosity control for the fpx Fortran preprocessor

This tiny but essential module that provides a single public logical flag verbose to enable or disable detailed diagnostic output throughout the entire fpx tool (parser, macro expansion, include handling, conditional compilation, etc.).

When verbose = .true., the preprocessor prints extensive debugging information such as:

• Currently processed file and line number
• Active conditional blocks
• Macro expansions (before/after)
• Include file resolution
• Directive handling
• Internal state changes

This is extremely useful during development, testing, and when debugging complex macro or include issues in large Fortran projects.

The flag is intentionally public and module-level so it can be set from anywhere (command-line driver, interactive mode, or library user).

Examples

1. Enable verbose output from the main program:

   verbose = .true.           ! Turn on all diagnostic messages
   call preprocess('src/main.F90', 'build/main.f90')
   ...

2. Temporarily enable verbosity for a single file processing:

   verbose = .true.
   call preprocess('debug_this.F90')
   verbose = .false.          ! Turn off again
   ...

3. Interactive session with full insight:

   $ fpx -v input.F90
   !> (implementation sets verbose = .true. from command-line “-v”)
   !> You will see every macro expansion, #ifdef state, include path, etc.

Variables

verbose

logical, public verbose

Master switch for verbose diagnostic output Default value is .false. (quiet mode). Set to .true. to get detailed step-by-step information about preprocessing actions. Safe to modify at any time – the change takes effect immediately for all subsequent operations.

Definition at line 56 of file logging.f90.