fgof-lineedit

Fortran-native line editing helpers for interactive CLI tools.

fgof-lineedit is intended to be a small, standalone library that gives Fortran shells, REPLs, and interactive CLIs a friendlier editing surface than raw terminal reads.

It is part of the FortranGoingOnForty lib-modules catalog, but it is intended to stand on its own as a normal fpm package.

Current v1 target:

• editable line buffer and cursor model
• prompt handling and rendered line state
• history navigation and history storage hooks
• completion and key-handling integration points
• clean boundaries with future fgof-termios and fgof-keys

Future scope:

• richer readline-style editing commands
• completion engines and menu UIs
• prompt widgets and multi-line editing

Status

Initial scaffold is in place.

Implemented today:

• public fgof_lineedit and fgof_lineedit_types modules
• line editor and prompt-state types
• prompt constructor, editable buffer core, cursor movement helpers, and history navigation
• smoke-test coverage and CI wiring

Still to implement:

• completion hooks
• terminal integration and redraw behavior

Why Use It

• line editing is repeatedly hand-built in shells, REPLs, and text tools
• the Fortran ecosystem still lacks an obvious small default package here
• it is meant to compose cleanly with fgof-pty, future fgof-termios, and future fgof-keys

Public API Shape

Primary modules:

• fgof_lineedit
• fgof_lineedit_types

Public types:

• lineedit_state
• prompt_spec
• history_entry

Current public procedures:

• add_history_entry
• buffer_length
• set_buffer
• insert_text
• delete_left
• delete_right
• default_prompt
• history_count
• history_previous
• history_next
• init_lineedit
• move_cursor_left
• move_cursor_right
• move_cursor_home
• move_cursor_end
• reset_lineedit

Quick Start

program demo_lineedit
  use fgof_lineedit, only : add_history_entry, default_prompt, history_previous, init_lineedit, lineedit_state
  implicit none

  type(lineedit_state) :: editor

  call init_lineedit(editor, default_prompt("> "))
  call add_history_entry(editor, "build")
  call history_previous(editor)
  print "(A)", editor%buffer
end program demo_lineedit

Build And Test

fpm test

That is the baseline verification command locally and in CI.

Supported Platforms

• macOS
• Linux

Boundaries

• intended to stay independently versioned and releasable
• focused on editing state and library ergonomics, not full shell implementation
• terminal-mode control should stay in a future companion package

License

MIT