1 | // Copyright (c) 2019-2023 Alexander Medvednikov. All rights reserved. |
2 | // Use of this source code is governed by an MIT license |
3 | // that can be found in the LICENSE file. |
4 | // |
5 | // TODO Windows version needs to be implemented. |
6 | // Will serve as more advanced input method |
7 | // based on the work of https://github.com/AmokHuginnsson/replxx |
8 | // |
9 | module readline |
10 | |
11 | import os |
12 | |
13 | // needed for parity with readline_default.c.v |
14 | struct Termios { |
15 | } |
16 | |
17 | // Only use standard os.get_line |
18 | // Need implementation for readline capabilities |
19 | // |
20 | // read_line_utf8 blocks execution in a loop and awaits user input |
21 | // characters from a terminal until `EOF` or `Enter` key is encountered |
22 | // in the input stream. |
23 | // read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or |
24 | // an error if the line is empty. |
25 | // The `prompt` `string` is output as a prefix text for the input capturing. |
26 | // read_line_utf8 is the main method of the `readline` module and `Readline` struct. |
27 | pub fn (mut r Readline) read_line_utf8(prompt string) ![]rune { |
28 | r.current = []rune{} |
29 | r.cursor = 0 |
30 | r.prompt = prompt |
31 | r.search_index = 0 |
32 | if r.previous_lines.len <= 1 { |
33 | r.previous_lines << []rune{} |
34 | r.previous_lines << []rune{} |
35 | } else { |
36 | r.previous_lines[0] = []rune{} |
37 | } |
38 | print(r.prompt) |
39 | r.current = os.get_raw_line().runes() |
40 | r.previous_lines[0] = []rune{} |
41 | r.search_index = 0 |
42 | if r.current.len == 0 { |
43 | return error('empty line') |
44 | } |
45 | return r.current |
46 | } |
47 | |
48 | // read_line does the same as `read_line_utf8` but returns user input as a `string`. |
49 | // (As opposed to `[]rune` returned by `read_line_utf8`). |
50 | pub fn (mut r Readline) read_line(prompt string) !string { |
51 | s := r.read_line_utf8(prompt)! |
52 | return s.string() |
53 | } |
54 | |
55 | // read_line_utf8 blocks execution in a loop and awaits user input |
56 | // characters from a terminal until `EOF` or `Enter` key is encountered |
57 | // in the input stream. |
58 | // read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or |
59 | // an error if the line is empty. |
60 | // The `prompt` `string` is output as a prefix text for the input capturing. |
61 | // read_line_utf8 is the main method of the `readline` module and `Readline` struct. |
62 | // NOTE that this version of `read_line_utf8` is a standalone function without |
63 | // persistent functionalities (e.g. history). |
64 | pub fn read_line_utf8(prompt string) ![]rune { |
65 | mut r := Readline{} |
66 | s := r.read_line_utf8(prompt)! |
67 | return s |
68 | } |
69 | |
70 | // read_line does the same as `read_line_utf8` but returns user input as a `string`. |
71 | // (As opposed to `[]rune` as returned by `read_line_utf8`). |
72 | // NOTE that this version of `read_line` is a standalone function without |
73 | // persistent functionalities (e.g. history). |
74 | pub fn read_line(prompt string) !string { |
75 | mut r := Readline{} |
76 | s := r.read_line(prompt)! |
77 | return s |
78 | } |