Sequence Tool

The Sequence Tool extension for Visual Studio Code allows you to easily insert custom sequences with a live preview.

Features

Insert Custom Sequence With Multi-cursors - sequence-tool.insertSequence

To insert a custom sequence using multi-cursors, use the following keyboard shortcut:

• Windows/Linux: Ctrl + Alt + 0,
• Mac: Cmd + Alt + 0

Note: Linebreak insertion is not supported with this command. Instead, use sequence-tool.insertNLinesAfter.

Insert N Lines After Cursors - sequence-tool.insertNLinesAfter

This command allows you to insert N lines after the cursor(s) and creates N new cursors on each line inserted.

Use Previous Saved Commands - sequence-tool.useCommand

You can defined custom commands from the settings sequence-tool.customCommands. These commands will be accessible through the sequence-tool.useCommand command and can be invoked via keybindings.

Example

1. Basic Usage

• To create a basic sequence, simply use the initial value:

  42           // 42, 43, 44, 45, ...
  

2. Padding

• Add padding to the sequence using the following syntax:

  #<5,42       // 42###, 43###, ...
  

3. Step

• To create a sequence with custom step size, use the third parameter:

  #<5,42,p+0.3 // 42.0#, 42.3#, 42.6#, ...
  

4. Base conversion

• Binary number with 0 padding uses 2's complement for negative numbers:

  04b,-3       // 1101, 1110, 1111, 0000, 0001, ...
  

• ASCII/Unicode representation:

  c,65         // A, B, C, D, E, ...
  

5. Other Practical Use

• Repeated character N times:

  #>3,,''      // ###, ###, ###, ...
  

• Cyclic and repeated values:

  ,,'123'[(i/4|0)%3] // 1,1,1,1, 2,2,2,2, 3,3,3,3, 1,...
  

• Spreadsheet column names:

  AZ           // AZ, BA, BB, BC, ...
  

• Early stopping:

  ,,i<5?p+1:'' // 0, 1, 2, 3, 4, 5 (index starts from 1 after init)
  

6. Custom Sequence

• Using the previous value in the sequence (similar to Array.prototype.reduce):

  ,1,p*2 (Power of 2)

• Cyclic pattern using an index (0-based):

  ,,['Sun','Mon','Tue','Wed','Thu','Fri','Sat'][i%7]

• Using both the previous value and index:

  ,1,p*(i+1) (factorial)

• Fibonacci sequence: d,,(((1+Math.sqrt(5))/2)**i-((1-Math.sqrt(5))/2)**i)/Math.sqrt(5)

• Catalan number: ,1,(4-6/(i+2))*p

  Alternatively: ,,(f=>f(f))(c=>x=>x?(4+6/~x)*(f=>f(f))(c)(x-1):1)(i)

• Look and say sequence: ,1,`${p}`.replace(/(.)\1*/g, m=>`${m.length}${m.substring(0, 1)}`)

Command Syntax

The extension supports a variety of formatting options using a subset of Python's format specification mini-language. The syntax for the command is as follows:

[[[fillChar]align][width][.prec][spec]],[init],[expr]

The command can either contain only the [init] field or separate the possibly empty field with ,.

Spec

The spec field allows you to customize how the sequence values are displayed.

Here are some format specifiers:

Init

Expr

You can customize how the next value of the sequence is generated using the expr field. The function (p, i) => expr allows you to define the logic for generating the next value.

For example, to generate a sequence with a step size of 2, you can use (p, i) => p + 2.

Extension Settings

This extension contributes the following settings:

• sequence-tool.customCommands: Store your frequently used commands here. These commands will appear in the sequence-tool.useCommand command and can be invoked through keybindings.

Example

Example Settings:

Keybindings

You can invoke commands through custom keybindings. Access the keybindings JSON by selecting Preferences: Open Keyboard Shortcuts (JSON).

Example keybindings for the factorial command and the preconfigured Catalan number command:

// Execute a command (factorial) on keypress
{
   "key": "ctrl+alt+,",
   "command": "sequence-tool.insertSequence",
   "args": { "command": ",1,p*(i+1)" }
},
// Pick a preconfigured command (Catalan numbers) on keypress
{
  "key": "ctrl+alt+.",
  "command": "sequence-tool.useCommand",
  "args": { "name": "Catalan" }
}

Release Notes

See CHANGELOG.md.

Special Thanks!

• Special thanks to tomoki1207/vscode-input-sequence for the live preview functionality.