Util.format-like unescaped string formatting utility based on quick-format-unescaped.
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npm install @visulima/fmtyarn add @visulima/fmtpnpm add @visulima/fmtimport { format } from "@visulima/fmt";
const formatted = format("hello %s %j %d", ["world", [{ obj: true }, 4, { another: "obj" }]]);
console.log(formatted); // hello world [{"obj":true},4,{"another":"obj"}] NaNA printf-like format string. Example: 'hello %s %j %d'
Array of values to be inserted into the format string. Example: ['world', {obj:true}]
Passing an options object as the third parameter with a stringify will mean
any objects will be passed to the supplied function instead of an the
internal tryStringify function. This can be useful when using augmented
capability serializers such as fast-safe-stringify or fast-redact.
uses
JSON.stringifyinstead ofutil.inspect, this means functions will not be serialized.
With the build function you can generate a format function that is optimized for your use case.
import { build } from "@visulima/fmt";
const format = build({
formatters: {
// Pass in whatever % interpolator you want, as long as it's a single character;
// in this case, it's `t`.
// The formatter should be a function that takes in a value and returns the formatted value.
t: (time) => new Date(time).toLocaleString(),
},
});
const formatted = format("hello %s at %t", ["world", Date.now()]);
console.log(formatted); // hello world at 1/1/1970, 1:00:00 AMFormat specifiers are dependent on the type of data-elements that are to be added to the string. The most commonly used format specifiers supported are:
| Specifier | Description |
|---|---|
| %s | Converts all values except for BigInt, -0 and Object to a string. |
| %d | Used to convert any value to Number of any type other than BigInt and Symbol. |
| %i | Used for all values except BigInt and Symbol. |
| %f | Used to convert a value to type Float. It does not support conversion of values of type Symbol. |
| %j | Used to add JSON data. If a circular reference is present, the string ‘[Circular]’ is added instead. |
| %o | Adds the string representation of an object. Note that it does not contain non-enumerable characteristics of the object. |
| %O | Adds the string representation of an object. Note that it will contain all characteristics of the object, including non-enumerable ones. |
| %c | Will parse basic CSS from the substitution subject like color: red into ANSI color codes. These codes will then be placed where the %c specifier is. Supported CSS properties are color, background-color, font-weight, font-style, text-decoration, text-decoration-color, and text-decoration-line. Unsupported CSS properties are ignored. An empty %c CSS string substitution will become an ANSI style reset. If color is disabled, %c is ignored. |
| %% | Used to add the % sign. |
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The visulima fmt is open-sourced software licensed under the MIT