From f5c4671bfbad96bf346bd7e9a21fc4317b4959df Mon Sep 17 00:00:00 2001 From: Indrajith K L Date: Sat, 3 Dec 2022 17:00:20 +0530 Subject: Adds most of the tools --- v_windows/v/vlib/readline/README.md | 20 + v_windows/v/vlib/readline/readline.v | 45 ++ v_windows/v/vlib/readline/readline_default.c.v | 78 ++++ v_windows/v/vlib/readline/readline_linux.c.v | 554 +++++++++++++++++++++++++ v_windows/v/vlib/readline/readline_test.v | 20 + v_windows/v/vlib/readline/readline_windows.c.v | 74 ++++ 6 files changed, 791 insertions(+) create mode 100644 v_windows/v/vlib/readline/README.md create mode 100644 v_windows/v/vlib/readline/readline.v create mode 100644 v_windows/v/vlib/readline/readline_default.c.v create mode 100644 v_windows/v/vlib/readline/readline_linux.c.v create mode 100644 v_windows/v/vlib/readline/readline_test.v create mode 100644 v_windows/v/vlib/readline/readline_windows.c.v (limited to 'v_windows/v/vlib/readline') diff --git a/v_windows/v/vlib/readline/README.md b/v_windows/v/vlib/readline/README.md new file mode 100644 index 0000000..edd4682 --- /dev/null +++ b/v_windows/v/vlib/readline/README.md @@ -0,0 +1,20 @@ +# Readline + +The `readline` module let you await and read user input +from a terminal in an easy and structured manner. + +The module provides an easy way to prompt the user for +questions or even make a REPL or an embedded console. + +Use `readline.Readline` if you want to include more +advanced features such as history or simply use +`readline.read_line('Please confirm (y/n):')` directly +for one-off user interactions. + +# Usage + +```v ignore +import readline { Readline } + +Readline.read_line('Continue?: (y/n)') +``` diff --git a/v_windows/v/vlib/readline/readline.v b/v_windows/v/vlib/readline/readline.v new file mode 100644 index 0000000..4f0ebf7 --- /dev/null +++ b/v_windows/v/vlib/readline/readline.v @@ -0,0 +1,45 @@ +// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved. +// Use of this source code is governed by an MIT license +// that can be found in the LICENSE file. +// +// Serves as a more advanced input method +// based on the work of https://github.com/AmokHuginnsson/replxx +// +module readline + +// Termios stores the terminal options on Linux. +struct C.termios {} + +struct Termios { +mut: + c_iflag int + c_oflag int + c_cflag int + c_lflag int + c_cc [12]int // NCCS == 12. Can't use the defined value here +} + +// Winsize stores the screen information on Linux. +struct Winsize { + ws_row u16 + ws_col u16 + ws_xpixel u16 + ws_ypixel u16 +} + +// Readline is the key struct for reading and holding user input via a terminal. +// Example: import readline { Readline } +pub struct Readline { +mut: + is_raw bool + orig_termios Termios // Linux + current []rune // Line being edited + cursor int // Cursor position + overwrite bool + cursor_row_offset int + prompt string + prompt_offset int + previous_lines [][]rune + search_index int + is_tty bool +} diff --git a/v_windows/v/vlib/readline/readline_default.c.v b/v_windows/v/vlib/readline/readline_default.c.v new file mode 100644 index 0000000..fcbbbb6 --- /dev/null +++ b/v_windows/v/vlib/readline/readline_default.c.v @@ -0,0 +1,78 @@ +// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved. +// Use of this source code is governed by an MIT license +// that can be found in the LICENSE file. +// +// TODO Mac version needs to be implemented +// Will serve as more advanced input method +// based on the work of https://github.com/AmokHuginnsson/replxx +// +module readline + +import os + +#include +// Only use standard os.get_line +// Need implementation for readline capabilities +// +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +pub fn (mut r Readline) read_line_utf8(prompt string) ?[]rune { + r.current = []rune{} + r.cursor = 0 + r.prompt = prompt + r.search_index = 0 + if r.previous_lines.len <= 1 { + r.previous_lines << []rune{} + r.previous_lines << []rune{} + } else { + r.previous_lines[0] = []rune{} + } + print(r.prompt) + line := os.get_raw_line() + if line.len >= 0 { + r.current = line.runes() + } + r.previous_lines[0] = []rune{} + r.search_index = 0 + if r.current.len == 0 { + return error('empty line') + } + return r.current +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` returned by `read_line_utf8`). +pub fn (mut r Readline) read_line(prompt string) ?string { + s := r.read_line_utf8(prompt) ? + return s.string() +} + +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +// NOTE that this version of `read_line_utf8` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line_utf8(prompt string) ?[]rune { + mut r := Readline{} + s := r.read_line_utf8(prompt) ? + return s +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` as returned by `read_line_utf8`). +// NOTE that this version of `read_line` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line(prompt string) ?string { + mut r := Readline{} + s := r.read_line(prompt) ? + return s +} diff --git a/v_windows/v/vlib/readline/readline_linux.c.v b/v_windows/v/vlib/readline/readline_linux.c.v new file mode 100644 index 0000000..eb0fda9 --- /dev/null +++ b/v_windows/v/vlib/readline/readline_linux.c.v @@ -0,0 +1,554 @@ +// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved. +// Use of this source code is governed by an MIT license +// that can be found in the LICENSE file. +// +// Serves as more advanced input method +// based on the work of https://github.com/AmokHuginnsson/replxx +// +module readline + +import term +import os + +#include +#include + +fn C.tcgetattr(fd int, termios_p &C.termios) int + +fn C.tcsetattr(fd int, optional_actions int, termios_p &C.termios) int + +fn C.raise(sig int) + +fn C.getppid() int + +// Action defines what actions to be executed. +enum Action { + eof + nothing + insert_character + commit_line + delete_left + delete_right + move_cursor_left + move_cursor_right + move_cursor_begining + move_cursor_end + move_cursor_word_left + move_cursor_word_right + history_previous + history_next + overwrite + clear_screen + suspend +} + +// enable_raw_mode enables the raw mode of the terminal. +// In raw mode all key presses are directly sent to the program and no interpretation is done. +// Please note that `enable_raw_mode` catches the `SIGUSER` (CTRL + C) signal. +// For a method that does please see `enable_raw_mode_nosig`. +pub fn (mut r Readline) enable_raw_mode() { + if C.tcgetattr(0, unsafe { &C.termios(&r.orig_termios) }) == -1 { + r.is_tty = false + r.is_raw = false + return + } + mut raw := r.orig_termios + raw.c_iflag &= ~(C.BRKINT | C.ICRNL | C.INPCK | C.ISTRIP | C.IXON) + raw.c_cflag |= C.CS8 + raw.c_lflag &= ~(C.ECHO | C.ICANON | C.IEXTEN | C.ISIG) + raw.c_cc[C.VMIN] = 1 + raw.c_cc[C.VTIME] = 0 + C.tcsetattr(0, C.TCSADRAIN, unsafe { &C.termios(&raw) }) + r.is_raw = true + r.is_tty = true +} + +// enable_raw_mode_nosig enables the raw mode of the terminal. +// In raw mode all key presses are directly sent to the program and no interpretation is done. +// Please note that `enable_raw_mode_nosig` does not catch the `SIGUSER` (CTRL + C) signal +// as opposed to `enable_raw_mode`. +pub fn (mut r Readline) enable_raw_mode_nosig() { + if C.tcgetattr(0, unsafe { &C.termios(&r.orig_termios) }) == -1 { + r.is_tty = false + r.is_raw = false + return + } + mut raw := r.orig_termios + raw.c_iflag &= ~(C.BRKINT | C.ICRNL | C.INPCK | C.ISTRIP | C.IXON) + raw.c_cflag |= C.CS8 + raw.c_lflag &= ~(C.ECHO | C.ICANON | C.IEXTEN) + raw.c_cc[C.VMIN] = 1 + raw.c_cc[C.VTIME] = 0 + C.tcsetattr(0, C.TCSADRAIN, unsafe { &C.termios(&raw) }) + r.is_raw = true + r.is_tty = true +} + +// disable_raw_mode disables the raw mode of the terminal. +// For a description of raw mode please see the `enable_raw_mode` method. +pub fn (mut r Readline) disable_raw_mode() { + if r.is_raw { + C.tcsetattr(0, C.TCSADRAIN, unsafe { &C.termios(&r.orig_termios) }) + r.is_raw = false + } +} + +// read_char reads a single character. +pub fn (r Readline) read_char() int { + return utf8_getchar() +} + +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +pub fn (mut r Readline) read_line_utf8(prompt string) ?[]rune { + r.current = []rune{} + r.cursor = 0 + r.prompt = prompt + r.search_index = 0 + r.prompt_offset = get_prompt_offset(prompt) + if r.previous_lines.len <= 1 { + r.previous_lines << []rune{} + r.previous_lines << []rune{} + } else { + r.previous_lines[0] = []rune{} + } + if !r.is_raw { + r.enable_raw_mode() + } + print(r.prompt) + for { + C.fflush(C.stdout) + c := r.read_char() + a := r.analyse(c) + if r.execute(a, c) { + break + } + } + r.previous_lines[0] = []rune{} + r.search_index = 0 + r.disable_raw_mode() + if r.current.len == 0 { + return error('empty line') + } + return r.current +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` returned by `read_line_utf8`). +pub fn (mut r Readline) read_line(prompt string) ?string { + s := r.read_line_utf8(prompt) ? + return s.string() +} + +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +// NOTE that this version of `read_line_utf8` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line_utf8(prompt string) ?[]rune { + mut r := Readline{} + s := r.read_line_utf8(prompt) ? + return s +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` as returned by `read_line_utf8`). +// NOTE that this version of `read_line` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line(prompt string) ?string { + mut r := Readline{} + s := r.read_line(prompt) ? + return s +} + +// analyse returns an `Action` based on the type of input byte given in `c`. +fn (r Readline) analyse(c int) Action { + match byte(c) { + `\0`, 0x3, 0x4, 255 { + return .eof + } // NUL, End of Text, End of Transmission + `\n`, `\r` { + return .commit_line + } + `\f` { + return .clear_screen + } // CTRL + L + `\b`, 127 { + return .delete_left + } // BS, DEL + 27 { + return r.analyse_control() + } // ESC + 1 { + return .move_cursor_begining + } // ^A + 5 { + return .move_cursor_end + } // ^E + 26 { + return .suspend + } // CTRL + Z, SUB + else { + if c >= ` ` { + return Action.insert_character + } + return Action.nothing + } + } +} + +// analyse_control returns an `Action` based on the type of input read by `read_char`. +fn (r Readline) analyse_control() Action { + c := r.read_char() + match byte(c) { + `[` { + sequence := r.read_char() + match byte(sequence) { + `C` { return .move_cursor_right } + `D` { return .move_cursor_left } + `B` { return .history_next } + `A` { return .history_previous } + `1` { return r.analyse_extended_control() } + `2`, `3` { return r.analyse_extended_control_no_eat(byte(sequence)) } + else {} + } + } + else {} + } + /* + //TODO +match c { + case `[`: + sequence := r.read_char() + match sequence { + case `C`: return .move_cursor_right + case `D`: return .move_cursor_left + case `B`: return .history_next + case `A`: return .history_previous + case `1`: return r.analyse_extended_control() + case `2`: return r.analyse_extended_control_no_eat(sequence) + case `3`: return r.analyse_extended_control_no_eat(sequence) + case `9`: + foo() + bar() + else: + } + else: +} + */ + return .nothing +} + +// analyse_extended_control returns an `Action` based on the type of input read by `read_char`. +// analyse_extended_control specialises in cursor control. +fn (r Readline) analyse_extended_control() Action { + r.read_char() // Removes ; + c := r.read_char() + match byte(c) { + `5` { + direction := r.read_char() + match byte(direction) { + `C` { return .move_cursor_word_right } + `D` { return .move_cursor_word_left } + else {} + } + } + else {} + } + return .nothing +} + +// analyse_extended_control_no_eat returns an `Action` based on the type of input byte given in `c`. +// analyse_extended_control_no_eat specialises in detection of delete and insert keys. +fn (r Readline) analyse_extended_control_no_eat(last_c byte) Action { + c := r.read_char() + match byte(c) { + `~` { + match last_c { + `3` { return .delete_right } // Suppr key + `2` { return .overwrite } + else {} + } + } + else {} + } + return .nothing +} + +// execute executes the corresponding methods on `Readline` based on `a Action` and `c int` arguments. +fn (mut r Readline) execute(a Action, c int) bool { + match a { + .eof { return r.eof() } + .insert_character { r.insert_character(c) } + .commit_line { return r.commit_line() } + .delete_left { r.delete_character() } + .delete_right { r.suppr_character() } + .move_cursor_left { r.move_cursor_left() } + .move_cursor_right { r.move_cursor_right() } + .move_cursor_begining { r.move_cursor_begining() } + .move_cursor_end { r.move_cursor_end() } + .move_cursor_word_left { r.move_cursor_word_left() } + .move_cursor_word_right { r.move_cursor_word_right() } + .history_previous { r.history_previous() } + .history_next { r.history_next() } + .overwrite { r.switch_overwrite() } + .clear_screen { r.clear_screen() } + .suspend { r.suspend() } + else {} + } + return false +} + +// get_screen_columns returns the number of columns (`width`) in the terminal. +fn get_screen_columns() int { + ws := Winsize{} + cols := if C.ioctl(1, C.TIOCGWINSZ, &ws) == -1 { 80 } else { int(ws.ws_col) } + return cols +} + +// shift_cursor warps the cursor to `xpos` with `yoffset`. +fn shift_cursor(xpos int, yoffset int) { + if yoffset != 0 { + if yoffset > 0 { + term.cursor_down(yoffset) + } else { + term.cursor_up(-yoffset) + } + } + // Absolute X position + print('\x1b[${xpos + 1}G') +} + +// calculate_screen_position returns a position `[x, y]int` based on various terminal attributes. +fn calculate_screen_position(x_in int, y_in int, screen_columns int, char_count int, inp []int) []int { + mut out := inp.clone() + mut x := x_in + mut y := y_in + out[0] = x + out[1] = y + for chars_remaining := char_count; chars_remaining > 0; { + chars_this_row := if (x + chars_remaining) < screen_columns { + chars_remaining + } else { + screen_columns - x + } + out[0] = x + chars_this_row + out[1] = y + chars_remaining -= chars_this_row + x = 0 + y++ + } + if out[0] == screen_columns { + out[0] = 0 + out[1]++ + } + return out +} + +// get_prompt_offset computes the length of the `prompt` `string` argument. +fn get_prompt_offset(prompt string) int { + mut len := 0 + for i := 0; i < prompt.len; i++ { + if prompt[i] == `\e` { + for ; i < prompt.len && prompt[i] != `m`; i++ { + } + } else { + len = len + 1 + } + } + return prompt.len - len +} + +// refresh_line redraws the current line, including the prompt. +fn (mut r Readline) refresh_line() { + mut end_of_input := [0, 0] + end_of_input = calculate_screen_position(r.prompt.len, 0, get_screen_columns(), r.current.len, + end_of_input) + end_of_input[1] += r.current.filter(it == `\n`).len + mut cursor_pos := [0, 0] + cursor_pos = calculate_screen_position(r.prompt.len, 0, get_screen_columns(), r.cursor, + cursor_pos) + shift_cursor(0, -r.cursor_row_offset) + term.erase_toend() + print(r.prompt) + print(r.current.string()) + if end_of_input[0] == 0 && end_of_input[1] > 0 { + print('\n') + } + shift_cursor(cursor_pos[0] - r.prompt_offset, -(end_of_input[1] - cursor_pos[1])) + r.cursor_row_offset = cursor_pos[1] +} + +// eof ends the line *without* a newline. +fn (mut r Readline) eof() bool { + r.previous_lines.insert(1, r.current) + r.cursor = r.current.len + if r.is_tty { + r.refresh_line() + } + return true +} + +// insert_character inserts the character `c` at current cursor position. +fn (mut r Readline) insert_character(c int) { + if !r.overwrite || r.cursor == r.current.len { + r.current.insert(r.cursor, c) + } else { + r.current[r.cursor] = rune(c) + } + r.cursor++ + // Refresh the line to add the new character + if r.is_tty { + r.refresh_line() + } +} + +// Removes the character behind cursor. +fn (mut r Readline) delete_character() { + if r.cursor <= 0 { + return + } + r.cursor-- + r.current.delete(r.cursor) + r.refresh_line() +} + +// suppr_character removes (suppresses) the character in front of the cursor. +fn (mut r Readline) suppr_character() { + if r.cursor >= r.current.len { + return + } + r.current.delete(r.cursor) + r.refresh_line() +} + +// commit_line adds a line break and then stops the main loop. +fn (mut r Readline) commit_line() bool { + r.previous_lines.insert(1, r.current) + r.current << `\n` + r.cursor = r.current.len + if r.is_tty { + r.refresh_line() + println('') + } + return true +} + +// move_cursor_left moves the cursor relative one cell to the left. +fn (mut r Readline) move_cursor_left() { + if r.cursor > 0 { + r.cursor-- + r.refresh_line() + } +} + +// move_cursor_right moves the cursor relative one cell to the right. +fn (mut r Readline) move_cursor_right() { + if r.cursor < r.current.len { + r.cursor++ + r.refresh_line() + } +} + +// move_cursor_begining moves the cursor to the beginning of the current line. +fn (mut r Readline) move_cursor_begining() { + r.cursor = 0 + r.refresh_line() +} + +// move_cursor_end moves the cursor to the end of the current line. +fn (mut r Readline) move_cursor_end() { + r.cursor = r.current.len + r.refresh_line() +} + +// is_break_character returns true if the character is considered as a word-breaking character. +fn (r Readline) is_break_character(c string) bool { + break_characters := ' \t\v\f\a\b\r\n`~!@#$%^&*()-=+[{]}\\|;:\'",<.>/?' + return break_characters.contains(c) +} + +// move_cursor_word_left moves the cursor relative one word length worth to the left. +fn (mut r Readline) move_cursor_word_left() { + if r.cursor > 0 { + for ; r.cursor > 0 && r.is_break_character(r.current[r.cursor - 1].str()); r.cursor-- { + } + for ; r.cursor > 0 && !r.is_break_character(r.current[r.cursor - 1].str()); r.cursor-- { + } + r.refresh_line() + } +} + +// move_cursor_word_right moves the cursor relative one word length worth to the right. +fn (mut r Readline) move_cursor_word_right() { + if r.cursor < r.current.len { + for ; r.cursor < r.current.len && r.is_break_character(r.current[r.cursor].str()); r.cursor++ { + } + for ; r.cursor < r.current.len && !r.is_break_character(r.current[r.cursor].str()); r.cursor++ { + } + r.refresh_line() + } +} + +// switch_overwrite toggles Readline `overwrite` mode on/off. +fn (mut r Readline) switch_overwrite() { + r.overwrite = !r.overwrite +} + +// clear_screen clears the current terminal window contents and positions the cursor at top left. +fn (mut r Readline) clear_screen() { + term.set_cursor_position(x: 1, y: 1) + term.erase_clear() + r.refresh_line() +} + +// history_previous sets current line to the content of the previous line in the history buffer. +fn (mut r Readline) history_previous() { + if r.search_index + 2 >= r.previous_lines.len { + return + } + if r.search_index == 0 { + r.previous_lines[0] = r.current + } + r.search_index++ + r.current = r.previous_lines[r.search_index] + r.cursor = r.current.len + r.refresh_line() +} + +// history_next sets current line to the content of the next line in the history buffer. +fn (mut r Readline) history_next() { + if r.search_index <= 0 { + return + } + r.search_index-- + r.current = r.previous_lines[r.search_index] + r.cursor = r.current.len + r.refresh_line() +} + +// suspend sends the `SIGSTOP` signal to the terminal. +fn (mut r Readline) suspend() { + is_standalone := os.getenv('VCHILD') != 'true' + r.disable_raw_mode() + if !is_standalone { + // We have to SIGSTOP the parent v process + ppid := C.getppid() + C.kill(ppid, C.SIGSTOP) + } + C.raise(C.SIGSTOP) + r.enable_raw_mode() + r.refresh_line() + if r.is_tty { + r.refresh_line() + } +} diff --git a/v_windows/v/vlib/readline/readline_test.v b/v_windows/v/vlib/readline/readline_test.v new file mode 100644 index 0000000..ab5154f --- /dev/null +++ b/v_windows/v/vlib/readline/readline_test.v @@ -0,0 +1,20 @@ +import readline { Readline } + +fn no_lines(s string) string { + return s.replace('\n', ' ') +} + +fn test_struct_readline() { + // mut rl := Readline{} + // eprintln('rl: $rl') + // line := rl.read_line('Please, enter your name: ') or { panic(err) } + // eprintln('line: $line') + mut methods := []string{} + $for method in Readline.methods { + // eprintln(' method: $method.name | ' + no_lines('$method')) + methods << method.name + } + // eprintln('methods: $methods') + assert 'read_line_utf8' in methods + assert 'read_line' in methods +} diff --git a/v_windows/v/vlib/readline/readline_windows.c.v b/v_windows/v/vlib/readline/readline_windows.c.v new file mode 100644 index 0000000..887efdb --- /dev/null +++ b/v_windows/v/vlib/readline/readline_windows.c.v @@ -0,0 +1,74 @@ +// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved. +// Use of this source code is governed by an MIT license +// that can be found in the LICENSE file. +// +// TODO Windows version needs to be implemented. +// Will serve as more advanced input method +// based on the work of https://github.com/AmokHuginnsson/replxx +// +module readline + +import os + +// Only use standard os.get_line +// Need implementation for readline capabilities +// +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +pub fn (mut r Readline) read_line_utf8(prompt string) ?[]rune { + r.current = []rune{} + r.cursor = 0 + r.prompt = prompt + r.search_index = 0 + if r.previous_lines.len <= 1 { + r.previous_lines << []rune{} + r.previous_lines << []rune{} + } else { + r.previous_lines[0] = []rune{} + } + print(r.prompt) + r.current = os.get_raw_line().runes() + r.previous_lines[0] = []rune{} + r.search_index = 0 + if r.current.len == 0 { + return error('empty line') + } + return r.current +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` returned by `read_line_utf8`). +pub fn (mut r Readline) read_line(prompt string) ?string { + s := r.read_line_utf8(prompt) ? + return s.string() +} + +// read_line_utf8 blocks execution in a loop and awaits user input +// characters from a terminal until `EOF` or `Enter` key is encountered +// in the input stream. +// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or +// an error if the line is empty. +// The `prompt` `string` is output as a prefix text for the input capturing. +// read_line_utf8 is the main method of the `readline` module and `Readline` struct. +// NOTE that this version of `read_line_utf8` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line_utf8(prompt string) ?[]rune { + mut r := Readline{} + s := r.read_line_utf8(prompt) ? + return s +} + +// read_line does the same as `read_line_utf8` but returns user input as a `string`. +// (As opposed to `[]rune` as returned by `read_line_utf8`). +// NOTE that this version of `read_line` is a standalone function without +// persistent functionalities (e.g. history). +pub fn read_line(prompt string) ?string { + mut r := Readline{} + s := r.read_line(prompt) ? + return s +} -- cgit v1.2.3