@origints/csv

CSV parsing with RFC 4180 support, header detection, predicate-based column lookup, and row filtering.

Installation

npm install @origints/csv @origints/core

Features

• RFC 4180 support (quoted fields, embedded newlines)
• Header row detection and column-by-name access
• Predicate-based column lookup (colWhere)
• Row filtering (rowsWhere) and row search (findRow)
• Type coercion (number, boolean) on demand
• Custom delimiters, quote characters, comments, and trim

Usage with Planner

Extract values from specific cells

import { Planner, loadFile, run } from '@origints/core'
import { parseCsv } from '@origints/csv'

const plan = new Planner()
  .in(loadFile('users.csv'))
  .mapIn(parseCsv({ header: true }))
  .emit((out, $) => out
    .add('firstName', $.row(0).col('name').string())
    .add('firstAge', $.row(0).col('age').number())
  )
  .compile()

const result = await run(plan, { readFile, registry })
// result.value: { firstName: 'Alice', firstAge: 30 }

Iterate over all rows

const plan = new Planner()
  .in(loadFile('users.csv'))
  .mapIn(parseCsv({ header: true }))
  .emit((out, $) => out
    .add('users', $.rows(row => ({
      kind: 'object',
      properties: {
        name: row.col('name').string(),
        age: row.col('age').number(),
        active: row.col('active').boolean(),
      },
    })))
  )
  .compile()

Column lookup by predicate

Find a column by matching its header:

import { col } from '@origints/csv'

$.rows(row => ({
  kind: 'object',
  properties: {
    revenue: row.colWhere(col.contains('Revenue')).number(),
    name: row.colWhere(col.equals('Company Name')).string(),
  },
}))

Filter rows by predicate

import { rowCol, col } from '@origints/csv'

$.rowsWhere(
  rowCol('status', col.equals('active')),
  row => ({
    kind: 'object',
    properties: {
      name: row.col('name').string(),
      dept: row.colWhere(col.contains('department')).string(),
    },
  })
)

Find a specific row

import { rowCol, col } from '@origints/csv'

$.findRow(rowCol('id', col.equals('ABC-123'))).col('email').string()

String predicates

import { col } from '@origints/csv'

col.equals('Revenue')              // exact match
col.contains('rev')                // substring (case-insensitive)
col.startsWith('Total')            // prefix
col.endsWith('USD')                // suffix
col.matches(/^Q[1-4] \d{4}$/)     // regex
col.isEmpty()                      // empty string
col.isNotEmpty()                   // non-empty

// Composition
col.contains('revenue').and(col.startsWith('total'))
col.equals('A').or(col.equals('B'))
col.isEmpty().not()

Standalone usage

import { parseCsvText } from '@origints/csv'

const table = parseCsvText('name,age\nAlice,30\nBob,25', { header: true })

for (const row of table) {
  const name = row.col('name')
  if (name.ok) console.log(name.value)
}

API

Export	Description
parseCsv(options?)	Transform AST for Planner.mapIn()
parseCsvText(input, options?)	Parse CSV string directly
registerCsvTransforms(registry)	Register CSV transforms
CsvTable	Table with row/column/cell access
CsvRow	Row with field access and type coercion
toJson(table, options?)	Convert to JSON
col	String predicate factory
rowCol, rowAt	Row predicate factories

License

MIT