fortrangoingonforty/fgof-lineedit / fc251b7

+# 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](https://github.com/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 and basic reset helper

+- smoke-test coverage and CI wiring

+

+Still to implement:

+

+- editable buffer operations

+- history and 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`

+

+Current public procedures:

+

+- `default_prompt`

+- `init_lineedit`

+- `reset_lineedit`

+

+## Quick Start

+

+```fortran

+program demo_lineedit

+  use fgof_lineedit, only : default_prompt, init_lineedit, lineedit_state

+  implicit none

+

+  type(lineedit_state) :: editor

+

+  call init_lineedit(editor, default_prompt("> "))

+  print "(A)", editor%prompt%text

+end program demo_lineedit

+```

+

+## Build And Test

+

+```bash

+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

+name = "fgof-lineedit"

+version = "0.1.0"

+license = "MIT"

+author = "FortranGoingOnForty"

+maintainer = "FortranGoingOnForty"

+copyright = "2026"

+description = "Fortran-native line editing helpers for interactive CLI tools"

+

+[build]

+auto-executables = false

+auto-tests = true

+auto-examples = false

+

+[install]

+library = true

+

+[fortran]

+implicit-typing = false

+implicit-external = false

+source-form = "free"

+module fgof_lineedit

+  use fgof_lineedit_types, only : lineedit_state, prompt_spec

+  implicit none

+  private

+

+  public :: default_prompt

+  public :: init_lineedit

+  public :: lineedit_state

+  public :: prompt_spec

+  public :: reset_lineedit

+

+contains

+

+  function default_prompt(text) result(prompt)

+    character(len=*), intent(in) :: text

+    type(prompt_spec) :: prompt

+

+    prompt%text = text

+  end function default_prompt

+

+  subroutine init_lineedit(editor, prompt)

+    type(lineedit_state), intent(out) :: editor

+    type(prompt_spec), intent(in), optional :: prompt

+

+    if (present(prompt)) then

+      editor%prompt = prompt

+    else

+      editor%prompt = default_prompt("> ")

+    end if

+

+    editor%buffer = ""

+    editor%cursor = 1

+    editor%active = .true.

+  end subroutine init_lineedit

+

+  subroutine reset_lineedit(editor)

+    type(lineedit_state), intent(inout) :: editor

+

+    editor%buffer = ""

+    editor%cursor = 1

+    editor%active = .false.

+  end subroutine reset_lineedit

+

+end module fgof_lineedit

+module fgof_lineedit_types

+  implicit none

+  private

+

+  public :: lineedit_state

+  public :: prompt_spec

+

+  type :: prompt_spec

+    character(len=:), allocatable :: text

+  end type prompt_spec

+

+  type :: lineedit_state

+    type(prompt_spec) :: prompt

+    character(len=:), allocatable :: buffer

+    integer :: cursor = 1

+    logical :: active = .false.

+  end type lineedit_state

+

+end module fgof_lineedit_types

+program test_scaffold

+  use fgof_lineedit, only : default_prompt, init_lineedit, lineedit_state, reset_lineedit

+  implicit none

+

+  type(lineedit_state) :: editor

+

+  call init_lineedit(editor, default_prompt("line> "))

+  if (.not. editor%active) error stop "editor should start active"

+  if (editor%prompt%text /= "line> ") error stop "editor should preserve prompt text"

+  if (editor%buffer /= "") error stop "editor should start with an empty buffer"

+  if (editor%cursor /= 1) error stop "editor should start with cursor at 1"

+

+  call reset_lineedit(editor)

+  if (editor%active) error stop "reset should deactivate the editor"

+  if (editor%buffer /= "") error stop "reset should clear the buffer"

+  if (editor%cursor /= 1) error stop "reset should restore cursor position"

+end program test_scaffold