How to run the program

In order to run this program one has to install Stack

One can download Stack here

Then to verify it works run:

stack run 

Before the program can be tested, we have to fill the database with data. There does exist a version to seed the data directly from the Scryfall API, however this takes about 20 minutes (80K object long JSON file that has to be parsed)

Therefore i have provided a smaller JSON file containing less cards. In order to seed the database with this you can use

stack run -- --seedFromFile

If you want to wait the full 20 minutes you can run the command

stack run -- --seedFromWeb

DSL

Will be a language based in set theory, where queries can be combined, negated etc etc.

It essentially is a Query Language, with similar properties as SQL. (It uses SQL at the bottom layer). So we have split the two Sets we can to into the following.

Query

A query is a very simple way of saying, limit all the cards in magic the gathering with the set limitation. Example there exists a Query function SuperType that takes in a string. This function will then match all cards type_line and return only those containing a match.

Operator

This is an operator between two sets. Example of an operator is the intersect operator. This takes two Sets and returns only the cards that exist in both. Example of a query using intersect:

(SuperType Creature) intersect (SuperType Legendary)

This query will only return Legendary Creatures, (Note: In theory you can write only (SuperType Legendary Creature) and it will return the same, however it is recommended to limit the SuperType search to only one word)

Avalible Query functions:

1. (CmcLT Int)
   • This function will find all cards with converted mana cost less than the Integer provided as input
2. (CmcMT Int)
   • This function will find all cards with converted mana cost more than the Integer provided as input
3. (CmcEQ Int)
   • This function will find all cards with converted mana cost equal to the Integer
4. (CmcLTEQ Int)
   • This function will find all cards with converted mana cost less than or equal to the Integer
5. (CmcMTEQ Int)
   • This function will find all cards with converted mana cost less than or equal to the Integer
6. (SuperType String)
   • This function will find all cards with the String value in its type_field.
   • NOTE: It is recommended to only use one word at a time and rather use set operators for better matching
7. (NotSuperType String)
   • This function will find all cards not containing the String value in its typefield
   • NOTE: It is recommended to only use one word at a time and rather use set operators for better matching
8. (Color String)
   • This function allows to find all cards containing specific color/colors.
   • VALID INPUT: [W,R,G,B,U] where U = Blue and B = Black
   • EX: a valid query is (Color WRG) fill find all cards that are White, Red and Black

Avalible Operators:

1. left intersect right
   • This operator will give the intersect of whatever is to the left and right of it.
   • Example: (SuperType Creature) intersect (Color R) = All Red Creatures
2. left union right
   • This operator will give the union of left and right
   • Example: (SuperType Creature) union (SuperType Instant) = All Creatures and Instants
3. left minus right
   • This operator will give you all cards present in left but not in right
   • Example: (SuperType Creature) union (SuperType Legendary) = All non Legendary Creatures

Example Queries

Here are some example queries and their expected results:

((SuperType Creature) intersect (SuperType Legendary)) intersect (CmcLTEQ 3) this query should return all Creatures that are also legendary with a converted mana cost less than or equal to three

(SuperType Enchantment) intersect (SuperType Creature) This should return all Enchantments that are also Creatures

(SuperType Creature) minus (SuperType Legendary) This should return all non legendary creatures.

Lexer

This languages lexer is very dumb. Therefore you the user has to be very verbose with your parenthesis. Example:

This will not work:

(IS Instant) union (Color Red) union (Color Green)

However this will

((IS Instant) union (Color Red)) union (Color Green)

The outer parenthesis is not needed, ex SuperType Creature is equivalent to (SuperType Creature)