Ast\_helper.Typ(3) OCaml library Ast\_helper.Typ(3)

# [NAME](#NAME)

Ast\_helper.Typ - Type expressions

# [Module](#Module)

Module Ast\_helper.Typ

# [Documentation](#Documentation)

Module **Typ**  
: **sig end**

Type expressions

*val mk* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs -> Parsetree.core\_type\_desc -> Parsetree.core\_type**

*val attr* : **Parsetree.core\_type -> Parsetree.attribute -> Parsetree.core\_type**

*val any* : **?loc:Ast\_helper.loc -> ?attrs:Ast\_helper.attrs -> unit -> Parsetree.core\_type**

*val var* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs -> string -> Parsetree.core\_type**

*val arrow* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Asttypes.arg\_label ->** **Parsetree.core\_type -> Parsetree.core\_type -> Parsetree.core\_type**

*val tuple* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **(string option * Parsetree.core\_type) list -> Parsetree.core\_type**

*val constr* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Ast\_helper.lid -> Parsetree.core\_type list -> Parsetree.core\_type**

*val object\_* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Parsetree.object\_field list -> Asttypes.closed\_flag -> Parsetree.core\_type**

*val class\_* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Ast\_helper.lid -> Parsetree.core\_type list -> Parsetree.core\_type**

*val alias* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Parsetree.core\_type -> string Ast\_helper.with\_loc -> Parsetree.core\_type**

*val variant* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Parsetree.row\_field list ->** **Asttypes.closed\_flag -> Asttypes.label list option -> Parsetree.core\_type**

*val poly* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Ast\_helper.str list -> Parsetree.core\_type -> Parsetree.core\_type**

*val package* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs -> Parsetree.package\_type -> Parsetree.core\_type**

*val open\_* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Ast\_helper.lid -> Parsetree.core\_type -> Parsetree.core\_type**

*val extension* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs -> Parsetree.extension -> Parsetree.core\_type**

*val functor\_* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Asttypes.arg\_label ->** **Ast\_helper.str ->** **Parsetree.package\_type -> Parsetree.core\_type -> Parsetree.core\_type**

*val force\_poly* : **Parsetree.core\_type -> Parsetree.core\_type**

*val varify\_constructors* : **Ast\_helper.str list -> Parsetree.core\_type -> Parsetree.core\_type**

**varify\_constructors newtypes te** is type expression **te** , of which any of nullary type constructor **tc** is replaced by type variable of the same name, if **tc** 's name appears in **newtypes** . Raise **Syntaxerr.Variable\_in\_scope** if any type variable inside **te** appears in **newtypes** .

**Since** 4.05

*val package\_type* : **?loc:Ast\_helper.loc ->** **?attrs:Ast\_helper.attrs ->** **Ast\_helper.lid ->** **(Ast\_helper.lid * Parsetree.core\_type) list -> Parsetree.package\_type**

**Since** 5.4

2026-10-23 OCamldoc

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Document: Ast_helper.Typ(3o) from ocaml 5.5.2-r0 (Chainguard OS)
Source: https://github.com/ocaml/ocaml