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This chapter will teach you to write queries without quasi-notation (such as [q|..|]). It is extremely optional and you may never want or need to use the normal notation, so feel free to skip past it.

To write a query without the quasi-quoter, you ned to use markers. They are simple abstract types that define the sort of thing you're querying for.

You can query for a component using C.

[qd|Name, Health|]

(C @Name, C @Health)

You can query for a relationship using R.

[qd|Likes -> *, ChildOf -> bob|]

(R @Likes Any, R @ChildOf bob)

You can run transitive queries using Q (or Q' to also provide a filter):

[qd|Likes -> (Name), ChildOf -> (Health / With Player)|]

(R @Likes (Q (C @Name)), R @ChildOf (Q' (C @Health) (With (C @Player))))

You can query for optional components using M. And for optional relationships using MR.

[qd|Maybe Name, Maybe Likes -> *|]

(M @Name, MR @Likes Any)

Each filter takes a single C or R type. They must be chained with And, Or, Not.

[qf|With Player, Without Likes -> * || !Changed Health|]

With (C @Player) `And` (Without (R @Likes Any) `Or` Not (Changed (C @Health)))

The q quasi-quoter will generate one of four functions, based on the following context:

If you query for components with no filter:

[q|Name, Health|]

mkQuery (C @Name, C @Health)

If you query for components with a filter:

[q|Name / With Player|]

mkQuery' (C @Name) (With (C @Player))

If you query for components of a specific entity with no filter:

[q|bob. Name, Health|]

mkGet bob (C @Name, C @Health)

If you query for components of a specific entity with a filter:

[q|bob. Name / With Player|]

mkGet' bob (C @Name) (With (C @Player))