1.6.1 Milestone Release

• New date/time formatting and parsing capability (issue #166)
• Support for comments in expressions (issue #75)
• Higher-order extension functions (issue #259)
• Allow Boolean to be cast to a number (issue #257)
• New functions
  • $eval - parse/evaluate the contexts of a JSON/JSONata string (issue #134)
  • $formatInteger - format an integer to a string using picture string definition
  • $parseInteger - parse an integer from a string using picture string definition
• Non-functional enhancements:
  • Split codebase into multiple files; fixed multiple issues with ES5 generated library
  • Multiple conformance tests in a single file
  • Documentation moved to main jsonata repo; generated using docusaurus.io
  • Minimum node.js runtime v6 (dropped support for v4)
• Numerous bug fixes (#236, #179, #261, #236, #245, #246, #233, #250, #247, #242, #249)

Note v1.6.0 was not released

1.5.4 Maintenance Release

• Fully test and fix bugs in async mode (PR #219)
• Publish Typescript definition file (issue #182)
• Numeric precision should be 15 decimal digits, not 13 (issue 194)
• Defining functions for use with $match etc. (issue #213)
• Fix regression in $substring for negative start position & length (issue #204)
• Fix for 'sort' syntax error (issue #210)
• Various code optimizations (issues #184, #205, #164)
• Add support for node 10.x (PR #228)

1.5.3 Maintenance Release

• $formatNumber should use zero-digit character for padding (issue #161)
• Handle undefined inputs in $formatNumber (issue #165)
• Handle surrogate pairs as single char in string functions (issue #156)
• Throw error if multiple group-by expressions evaluate to same key (issue #163)

1.5.2 Maintenance Release

• Enforce consistent syntax error when attempting to use unquoted numeric property names (issue #147)
• Invalid token on LHS of binding operator is now a syntax error rather than dynamic (runtime) error (issue #148)
• Fix corruption of predicated function calls within lambda functions (PR 149)

1.5.1 Maintenance Release

• Update $toMillis() to allow more complete range of ISO 8601 compatible dates (issue #140)
• Fix $append() so that it doesn't mutate the first argument (issue #139)

1.5.0 Milestone Release

• Restructured the entire test suite to be implementation language agnostic (PR #122)
• Provide es5 as main entry point, es6 as module entry point (PR #106)
• Added Typescript definitions to package (PR #114)
• Changes to how 'singleton sequences' are handled (issue #93)
• Unary negation of undefined (no match) should return undefined (issue #99)

1.4.1 Maintenance Release

• Object transformation syntax should work with arrays of objects as well as objects (issue #94)

1.4.0 Milestone Release

• New object transformation syntax ~> |...|...| (issue #70)
• New functions
  • $formatNumber - formats a decimal number to a string using a picture specification defined in XPath F&O spec (issue #54)
  • $formatBase - converts a number to a string in a specified radix
  • $pad - pads a string to a minimum width with leading or trailing padding characters
  • $toMillis - converts an ISO 8601 formatted date/time string to number of milliseconds since the epoch (issue #55)
  • $fromMillis - converts the number of milliseconds since the epoch to an ISO 8601 formatted date/time string (issue #55)
  • $clone - returns a deep copy of an object - used internally by the object transform syntax; overridable by custom implementation. Do not use directly in expressions. (issue #70)

1.3.3 Maintenance Release

• $lookup() function throws an error when the property has a null value (issue #85)

1.3.2 Maintenance Release

• Support extension functions that mix sync/async behaviours (issue #77)