Depend on OCaml 5.1.1+ (links-lang#1192)

This patch raises the lower bound of the dependency `ocaml` to 5.1.1 and
onwards.

We discussed this during the monthly Links Developer Meeting; and it
was agreed that we would raise the lower bound to OCaml 5 to encourage
the use of effect handlers to extend and simplify the code base.

.github/workflows/default.yml

@@ -17,7 +17,7 @@ jobs:
         os:
           - ubuntu-20.04
         ocaml-compiler:
-          - 4.14.1
+          - 5.1.1
 
     runs-on: ${{ matrix.os }}
 
@@ -71,8 +71,7 @@ jobs:
         os:
           - ubuntu-20.04
         ocaml-compiler:
-          - 4.14.1
-          - 5.0.0
+          - 5.1.1
 
     runs-on: ${{ matrix.os }}
 
@@ -113,8 +112,7 @@ jobs:
         os:
           - ubuntu-20.04
         ocaml-compiler:
-          - 4.14.1
-          - 5.0.0
+          - 5.1.1
 
     runs-on: ${{ matrix.os }}
 
@@ -202,8 +200,7 @@ jobs:
         os:
           - ubuntu-20.04
         ocaml-compiler:
-          - 4.14.1
-          - 5.0.0
+          - 5.1.1
 
     runs-on: ${{ matrix.os }}
 

CHANGES.md

@@ -1,5 +1,9 @@
 # Unreleased
 
+## Require OCaml 5.1.1
+
+The minimum required OCaml version has been raised to 5.1.1.
+
 # 0.9.8
 
 This release includes minor bug fixes, improvements, and a breaking change regarding the syntax of handlers.

INSTALL.md

@@ -2,12 +2,12 @@
 
 We recommend installing Links using the OPAM tool (version >= 2.1), available from [opam.ocaml.org](https://opam.ocaml.org/).
 
-Links requires at least OCaml 4.08.0 to build and install. Therefore
+Links requires at least OCaml 5.1.1 to build and install. Therefore
 you should first install the minimum (or greater) required version of
 OCaml:
 
 ```
-$ opam switch install 4.08.0
+$ opam switch create 5.1.1
 ```
 
 You can then install Links and its database drivers simply by issuing the commands:

dune-project

@@ -31,7 +31,7 @@
  (name links)
  (synopsis "The Links Programming Language")
  (description "Links is a functional programming language designed to make web programming easier.")
- (depends (ocaml (>= : 4.14.0))
+ (depends (ocaml (>= : 5.1.1))
           (dune-configurator (>= : 3.8))
            ppx_deriving
           (ppx_deriving_yojson (>= 3.3))

links.opam

@@ -23,7 +23,7 @@ doc: "https://links-lang.org/quick-help.html"
 bug-reports: "https://github.com/links-lang/links/issues"
 depends: [
   "dune" {>= "2.7"}
-  "ocaml" { >= "4.14.0"}
+  "ocaml" { >= "5.1.0"}
   "dune-configurator" { >= "3.8"}
   "ppx_deriving"
   "ppx_deriving_yojson" {>= "3.3"}