indent_and_wrap: Text utility for Deno

Finds and replaces common indent in text, and hard-wraps text.

Example

import {indentAndWrap} from 'https://deno.land/x/indent_and_wrap@v0.0.1/mod.ts';

console.log
(	indentAndWrap
    (	`	Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
        `,
        {wrapWidth: 40, indent: '\t'}
    )
);

Exported symbols

• calcLines() - Count number of lines in text string, and determine column number of the last character.
• findCommonIndent() - Scan text string, and find leading space characters, that are common across all lines.
• indentAndWrap() - Indent or unindent and wrap text.
• IndentAndWrapOptions

calcLines()

function calcLines(text: string, from=0, to=Number.MAX_SAFE_INTEGER, tabWidth=4): {nLine: number, nColumn: number}

Count number of lines in text string, and determine column number of the last character.

This function only considers text substring from from to to.

findCommonIndent()

function findCommonIndent(text: string, ignoreFirstIndent=false): string

Scan text string, and find leading space characters, that are common across all lines.

If ignoreFirstIndent is set, then the leading space on the first line is not counted, so the provided text string can be trimmed.

This function uses fast algorithm that avoids splitting text to lines array.

indentAndWrap()

function indentAndWrap(text: string, options?: IndentAndWrapOptions, knownCommonIndent?: string): string

type IndentAndWrapOptions =
{	indent?: string;
    ignoreFirstIndent?: boolean;
    wrapWidth?: number;
    tabWidth?: number;
    endl?: string;
};

This function does:

• Replaces new line characters (\n, \r\n or \r) to options.endl, or if it’s not set to \n.
• If options.indent is set, it determines common indent characters across all lines, and replaces them with options.indent string. This can lead to indent increase or decrease. If options.ignoreFirstIndent is set, will look for common indent starting at second line, so the text can be trimmed. If you already know the common indent (e.g. you called findCommonIndent()), you can provide it as knownCommonIndent to save some calculation time. If knownCommonIndent doesn’t match the result of findCommonIndent(), the behavior is undefined.
• If options.wrapWidth is set, it inserts options.endl, so there’re no lines longer than options.wrapWidth columns. Columns are calculated with respect to options.tabWidth (default 4).