Agda- A dependently typed functional programming language and proof assistant

Safe HaskellNone




The concrete syntax is a raw representation of the program text without any desugaring at all. This is what the parser produces. The idea is that if we figure out how to keep the concrete syntax around, it can be printed exactly as the user wrote it.



data Expr Source

Concrete expressions. Should represent exactly what the user wrote.


Ident QName

ex: x

Lit Literal

ex: 1 or "foo"

QuestionMark !Range (Maybe Nat)

ex: ? or {! ... !}

Underscore !Range (Maybe String)

ex: _ or _A_5

RawApp !Range [Expr]

before parsing operators

App !Range Expr (NamedArg Expr)

ex: e e, e {e}, or e {x = e}

OpApp !Range QName [OpApp Expr]

ex: e + e

WithApp !Range Expr [Expr]

ex: e | e1 | .. | en

HiddenArg !Range (Named String Expr)

ex: {e} or {x=e}

InstanceArg !Range (Named String Expr)

ex: {{e}} or {{x=e}}

Lam !Range [LamBinding] Expr

ex: \x {y} -> e or \(x:A){y:B} -> e

AbsurdLam !Range Hiding

ex: \ ()

ExtendedLam !Range [(LHS, RHS, WhereClause)]

ex: \ { p11 .. p1a -> e1 ; .. ; pn1 .. pnz -> en }

Fun !Range Expr Expr

ex: e -> e or .e -> e (NYI: {e} -> e)

Pi Telescope Expr

ex: (xs:e) -> e or {xs:e} -> e

Set !Range

ex: Set

Prop !Range

ex: Prop

SetN !Range Integer

ex: Set0, Set1, ..

Rec !Range [(Name, Expr)]

ex: record {x = a; y = b}

RecUpdate !Range Expr [(Name, Expr)]

ex: record e {x = a; y = b}

Let !Range [Declaration] Expr

ex: let Ds in e

Paren !Range Expr

ex: (e)

Absurd !Range

ex: () or {}, only in patterns

As !Range Name Expr

ex: x@p, only in patterns

Dot !Range Expr

ex: .p, only in patterns

ETel Telescope

only used for printing telescopes

QuoteGoal !Range Name Expr

ex: quoteGoal x in e

Quote !Range

ex: quote, should be applied to a name

QuoteTerm !Range

ex: quoteTerm, should be applied to a term

Unquote !Range

ex: unquote, should be applied to a term of type Term

DontCare Expr

to print irrelevant things

data OpApp e Source


SyntaxBindingLambda !Range [LamBinding] e

an abstraction inside a special syntax declaration (see Issue 358 why we introduce this).

Ordinary e 

fromOrdinary :: e -> OpApp e -> eSource

data AppView Source

The Expr is not an application.


AppView Expr [NamedArg Expr] 


data LamBinding Source

A lambda binding is either domain free or typed.


DomainFree Hiding Relevance BoundName

. x or {x} or .x or .{x} or {.x}

DomainFull TypedBindings

. (xs : e) or {xs : e}

data TypedBindings Source

A sequence of typed bindings with hiding information. Appears in dependent function spaces, typed lambdas, and telescopes.


TypedBindings !Range (Arg TypedBinding)

. (xs : e) or {xs : e}

type Telescope = [TypedBindings]Source

A telescope is a sequence of typed bindings. Bound variables are in scope in later types.


data Declaration Source

The representation type of a declaration. The comments indicate which type in the intended family the constructor targets.

type TypeSignature = DeclarationSource

Just type signatures.

type Constructor = TypeSignatureSource

A data constructor declaration is just a type signature.

data ImportDirective Source

The things you are allowed to say when you shuffle names between name spaces (i.e. in import, namespace, or open declarations).




importDirRange :: !Range
usingOrHiding :: UsingOrHiding
renaming :: [Renaming]
publicOpen :: Bool

Only for open. Exports the opened names from the current module.

data Renaming Source




renFrom :: ImportedName

Rename from this name.

renTo :: Name

To this one.

renToRange :: Range

The range of the "to" keyword. Retained for highlighting purposes.

data AsName Source




asName :: Name

The "as" name.

asRange :: Range

The range of the "as" keyword. Retained for highlighting purposes.

defaultImportDir :: ImportDirectiveSource

Default is directive is private (use everything, but do not export).

data LHS Source

Left hand sides can be written in infix style. For example:

 n + suc m = suc (n + m)
 (f ∘ g) x = f (g x)

We use fixity information to see which name is actually defined.



original pattern, with-patterns, rewrite equations and with-expressions


lhsOriginalPattern :: Pattern
f ps
lhsWithPattern :: [Pattern]

| p (many)

lhsRewriteEqn :: [RewriteEqn]

rewrite e (many)

lhsWithExpr :: [WithExpr]

with e (many)

Ellipsis Range [Pattern] [RewriteEqn] [WithExpr]

new with-patterns, rewrite equations and with-expressions

data Pattern Source

Concrete patterns. No literals in patterns at the moment.


IdentP QName

c or x

AppP Pattern (NamedArg Pattern)

p p' or p {x = p'}

RawAppP !Range [Pattern] before parsing operators

OpAppP !Range QName [Pattern]

eg: p => p' for operator _=>_

HiddenP !Range (Named String Pattern)

{p} or {x = p}

InstanceP !Range (Named String Pattern)

{{p}} or {{x = p}}

ParenP !Range Pattern
WildP !Range
AbsurdP !Range
AsP !Range Name Pattern

x@p unused

DotP !Range Expr
LitP Literal

0, 1, etc.

data LHSCore Source

Processed (scope-checked) intermediate form of the core f ps of LHS. Corresponds to lhsOriginalPattern.




lhsDestructor :: QName

record projection identifier

lhsPatsLeft :: [NamedArg Pattern]

side patterns

lhsFocus :: NamedArg LHSCore

main branch

lhsPatsRight :: [NamedArg Pattern]

side patterns

type Module = ([Pragma], [Declaration])Source

Modules: Top-level pragmas plus other top-level declarations.

topLevelModuleName :: Module -> TopLevelModuleNameSource

Computes the top-level module name.

Precondition: The Module has to be well-formed.

Pattern tools

patternHead :: Pattern -> Maybe NameSource

Get the leftmost symbol in a pattern.

patternNames :: Pattern -> [Name]Source

Get all the identifiers in a pattern in left-to-right order.