sql-tag.js

const $generated = Symbol('$generated')

function sql (strings, ...values) {
  let query = ''
  strings.forEach((string, i) => {
    query += string + (i < values.length ? '$' + (i + 1) : '')
  })
  query = query.replace(/^\s+/mg, '').trim()
  return [$generated, query, values]
}


function query ([safety, sql, params]) {
  if (safety !== $generated) {
    throw new Error('Must pass a sql-tagged string into query()')
  }
  // ...
}

// Works
query(sql`
  SELECT *
  FROM users
  WHERE email = lower(${'a'}) OR uname = ${'b'}
`)
// SELECT *
// FROM users
// WHERE email = $1 OR uname = $2
// , ['a', 'b']

// If you forget tag the query...
// Error: Must pass a sql-tagged string into query()
query(`
  SELECT *
  FROM users
  WHERE email = lower(${'a'}) OR uname = ${'b'}
`)