Line-oriented generated content

@stackline/update-section

Replace the first marker-delimited range, append or prepend a missing section, and inspect inclusive marker metadata through the familiar synchronous API.

npm install @stackline/update-section

v1.0.0Node 12-24TypeScript 3.9+Zero runtime dependencies

Real package execution

Section-replacement workbench

The documentation build bundles the package's real ESM entry. Every edit below calls that bundle; this is not a reimplementation of its marker algorithm.

Start marker text End marker text When start is absent

Original content

LF-delimited text

Replacement section

Markers included by caller

Updated content

`parse()` metadata

Inclusive indexes

Ready The package bundle is loading.

Small synchronous API

Callable replacement plus parse metadata.

Matchers receive each line, including a trailing carriage return when the input uses CRLF. Truthy results match and thrown values propagate.

API	Behavior	Status
`updateSection(content, section, start, end, top?)`	Replace the first start-through-end range, or insert when no start exists.	Preserved
`updateSection.parse(lines, start, end)`	Return `hasStart`, `hasEnd`, and inclusive indexes.	Preserved and corrected
`parse(...)`	Named ESM export for the same function.	Additive
`update-section.js`	Historical CommonJS deep entry.	Preserved

Narrow compatibility corrections

Metadata tells the truth.

Normal upstream output remains unchanged. The maintained package corrects the documented parser defects and one scale failure.

Inclusive end index. endIdx always identifies the last replaced input line.
Truthful end flag. hasEnd is true only when the end matcher succeeds.
Ordered markers. End markers before the selected start are observed by callbacks but do not form crossed ranges.
Large sections. Insertion avoids argument-count limits from Function.apply.

Release proof

Small code, explicit boundary matrix.

The published release passed upstream behavior, intentional-difference, public-entry, clean-consumer, package, audit, and documentation gates.

7: Node major lines from 12 through 24
3: operating systems in CI
0: runtime, optional, and peer dependencies
2: TypeScript generations checked
LF/CRLF: line values and separator behavior characterized
Browser: real bundle exercised by tests and this workbench

Drop-in adoption

Keep the historical package key.

The published npm alias lets existing require('update-section') calls resolve to the scoped package.

npm install update-section@npm:@stackline/update-section

Project resources