1 files changed, 59 insertions, 0 deletions
diff --git a/lib/expression/compose.mli b/lib/expression/compose.mli
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+++ b/lib/expression/compose.mli
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+(** Build an expression module with the result from another expression. The
+    signature of the fuctions is a bit different, as they all receive the
+    result from the previous evaluated element in argument. *)
+module Expression
+    (E : Sym.SYM_EXPR)
+    (_ : sig
+      val v : 'a E.path_repr
+    end) : sig
+  (** The signature for the module the adapt is a bit different for the
+      SYM_EXPR: every function takes an extra argument which is the Expression
+      we are wrapping, and every expression becomes a tuple with the same
+      expression represented in the composed type. *)
+  module type SIG = sig
+    type 'a repr
+    type 'a obs
+    type 'a path_repr
+
+    val empty : 'a E.obs -> 'a repr
+    val expr : 'a E.obs * 'a repr -> 'a E.obs -> 'a repr
+    val literal : string -> 'a E.obs -> 'a repr
+    val integer : string -> 'a E.obs -> 'a repr
+    val path : 'a path_repr -> 'a -> 'a E.obs -> 'a repr
+    val concat : ('a E.obs * 'a repr) list -> 'a E.obs -> 'a repr
+
+    val window :
+      ('a E.obs * 'a repr) T.window ->
+      ('a E.obs * 'a repr) list ->
+      ('a E.obs * 'a repr) list ->
+      'a E.obs ->
+      'a repr
+
+    val nvl : ('a E.obs * 'a repr) list -> 'a E.obs -> 'a repr
+    val join : string -> ('a E.obs * 'a repr) list -> 'a E.obs -> 'a repr
+
+    val boperator :
+      T.binary_operator ->
+      'a E.obs * 'a repr ->
+      'a E.obs * 'a repr ->
+      'a E.obs ->
+      'a repr
+
+    val gequality :
+      T.binary_operator ->
+      'a E.obs * 'a repr ->
+      ('a E.obs * 'a repr) list ->
+      'a E.obs ->
+      'a repr
+
+    val funct : string -> ('a E.obs * 'a repr) list -> 'a E.obs -> 'a repr
+    val function' : T.funct -> ('a E.obs * 'a repr) list -> 'a E.obs -> 'a repr
+    val observe : 'a E.obs * 'a repr -> 'a obs
+  end
+
+  module Make (M : SIG) :
+    Sym.SYM_EXPR
+      with type 'a obs = 'a M.obs
+       and type 'a repr = 'a E.repr * 'a M.repr
+       and type 'a path_repr = 'a M.path_repr
+end