Format

format and formatSafe serialize a LogicalExpression (or expression string) back to a canonical string.

Function signatures

function format(expression: string | LogicalExpression): string;

function formatSafe(
  expression: string | LogicalExpression,
): { type: "success"; result: string } | { type: "error"; error: ESCalcError };

Canonical output rules

Input syntax	Formatted output
`[name]`, `{name}`	`[name]`
Bare string literal	`'value'`
Number / boolean literal	Unchanged
Date literal `#YYYY-MM-DD#`	`#YYYY-MM-DD#`
Binary operators	Surrounded by single spaces: `a + b`
Ternary	`condition ? trueValue : falseValue`
`in` / `not in`	`left in right`, `left not in right`
Lists	Items joined by commas (no spaces): `1,2,3`

format does not add parentheses to disambiguate precedence; the output preserves the operator precedence implied by the AST structure.

Examples

import { format } from "@imogenz/escalc";

// Normalise whitespace
format("1+2"); // => '1 + 2'
format("  [x]  *  3"); // => '[x] * 3'

// Parameter bracket style normalisation
format("{myParam} + 1"); // => '[myParam] + 1'

// Round-trip: parse then format gives normalised form
format("[price]*(1+[tax])"); // => '[price] * 1 + [tax]'

Round-trip normaliser

Combine parse and format to normalise any expression to a canonical form before storing or displaying it:

import { format } from "@imogenz/escalc";

function normalise(expr: string): string {
  return format(expr);
}

normalise("  ( [x]+[y] ) * 2 "); // => '[x] + [y] * 2'

Safe usage

import { formatSafe } from "@imogenz/escalc";

const result = formatSafe(userInput);
if (result.type === "error") {
  console.error("Invalid expression:", result.error.message);
} else {
  console.log(result.result);
}