change-log.md

Lambda Calculator Change Log

2/2021 - 7/2022 (update to version 2.6.0)

Authors: Raef Khan, Kaustubh Ghoshal, Pinhan Zhao

1. Implemented Commutativity and Associativity

• Made the following operations commutative and associative: And, Or, Iff, Equality, Fusion, Multiplication, Set Union, Set Intersection.

2. Added Bracket Highlighting

• When brackets match, they are highlighted in green. If there are not enough brackets, the mismatched ones will highlight red.

3. Other bug fixes and features

• Fixed bugs #25 and #28
• Added input symbol for Set Union
• Parser now throws an error when a word is defined multiple times.
• Added brackets around product types to make them more explicit. Product types always bind more tightly than implicit comma.
• Fixed spacing issue with comma seperator when a composite type has a product type as one of the subtypes.

9/2020 - 1/2021 (update to version 2.5.0)

Authors: Anna Alsop, Raef Khan and Nigel Flower

1. Renamed "Lambda Abstraction" to "Predicate Abstraction"

• This was done to facilitate clarity with the textbook.

2. Fixed bug #23

• Implemented matching with variable types and constant types in student exercises.

3. Removed Save Dialogue on Reload

• In the teacher edition, when reloading a file, the GUI no longer asks the user to save unsaved work.

7/2020 - 8/2020 (update to version 2.4.0)

Authors: Anna Alsop and Raef Khan

1. Function composition

• New function composition rule added (issue #31)

2. Polymorphism revamp

• Polymorphism functionality enhanced for complex variable types

3. Other bug fixes and new features

• Variable types now display as Greek letters
• Reload function made compatible with unsuccessful loads (issue #27)
• Dialog window prompting user to save work before subsequent reload (issue #30)
• After reloading, the same exercise is selected.

5/2019 - 8/2019 (update to version 2.3.0)

Authors: Anna Alsop and Raef Khan

1. Launch4j exe packager

• Update launch4j
• Bundle java with exe file

2. Other bug fixes and new features

• All instances of primes are now printed as apostrophes
• Addressed issue #2, #21
• Fixed issue #14 (type parser bug)
• Capital letters can now be used for types
• Brought visual display of meaning bracket expressions in line with Coppock & Champollion textbook draft

3. Updates to wiki:

• New navigation menu
• Special Symbols and Exercise File Format pages newly created
• Polymorphism example exercise file added to wiki
• Related Projects section added to LambdaCalculator.com site
• Added override mode documentation to Exercise File Format page
• Exercise files may contain special symbols; documented in Exercise File Format page

Previous updates

2019-08-26: Version 2.3.0

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• fix type parser bug where types could not have two adjacent open brackets '<' (issue # 14)
• new error message generated when a type specification has an extra close bracket '>'
• capital letters can be used for types
• updated launch4j
• bundle java with exe file

2018-09-02: Version 2.2.0

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• fix loading of student exercises saved with traces
• add support applying functions with product types
• add support for nested product types
• open window goes to Downloads directory at beginning of session
• open window goes to previous open directory otherwise
• updated "About" window in Mac

2015-12-07: Version 2.1.0

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• replace [[ ]] with << >>

• choose variables based on indices, eliminating need for (explicitly represented) assignment fns

• functions wrapped in [ ] instead of ( )

• bracketing conventions now match Heim and Kratzer

• add support for *-ed constants

• add individual-level fusion, via +, and part-of, via <: (with Ctrl-: as interactive keyboard shortcut)

• single-letter identifiers off by default (since bound variables are now hardcoded to have multiple characters, e.g. v2)

• eliminate precedence conventions between and/or and if/iff

• infix grouping with [ ] instead of ( )

• apostrophe rather than ? indicates type var (e.g., <'at,t> rather than <?at,t>)

• treat cat nodes above dummy terms as dummies (fixes bug)

• reduce terms in all positions of an arglist (fixes bugs)

• match type vars with functional types to support, e.g., generalized junction (fixes bugs)

• display previous lambda conversion exercises when focused

2013-04-01: Version 2.0.0-beta

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• Codesigned Mac application to bypass Gatekeeper security checks
• Support for Intensional Function Application
• Traces and indices with arbitrary type specifications
• Export trees to LaTeX
• Support for polymorphic types on functions and arguments

2008-03-29: Version 1.0.12

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• Fixed alphabetical variants of { x | ... } notation.
• Fixed loading saved exercise files that use the new expression types.

2008-03-21: Version 1.0.11

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• Treat { x | ... } as a binder.
• In the scratch pad window, when there's a syntax error in the problem statement, move the cursor to the location of the problem.
• Allow the empty set symbol and raw integer numbers to be used in predicate logic expressions.

2008-03-20: Version 1.0.10

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1. Added to our predicate logic:
   • Set notations { a, b, c } and { ... | ... }.
   • Set intersection, union, subset, proper subset, superset, proper
   • superset, and cardinality.
   • Integer multiplication. This is for the 'most' generalized quantifier.
   • Integer greater than, less than, those + or equal.
2. Added a new example file and updated the documentation for generalized quantifiers.

Version 1.0.09

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• Allow omega and sigma symbols to be included in logical expressions.
• Improved the naming conventions display for multiple letter identifiers.
• In exercise files, parse multiple letter type conventions.
• Update docs and example file.

2008-01-30: Version 1.0.08

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• Corrected a problem reading exercise files saved in UTF8 with an initial byte order marker.
• Corrected a problem saving exercise files with meaning brackets.

2007-12-12: Version 1.0.07

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• Corrected a problem saving exercise files with identifier conventions without explicit description text.
• Fix typo-type mistakes in example2.txt

Previous releases

gh-pages branch: https://github.com/nyusemantics/LambdaCalculatorPublic/releases