SML: Step 0

Makefile.impls

@@ -36,7 +36,7 @@ IMPLS = ada ada.2 awk bash basic bbc-basic c chuck clojure coffee common-lisp cp
 	elisp elixir elm erlang es6 factor fantom fennel forth fsharp go groovy gnu-smalltalk \
 	guile haskell haxe hy io janet java js jq julia kotlin livescript logo lua make mal \
 	matlab miniMAL nasm nim objc objpascal ocaml perl perl6 php picolisp pike plpgsql \
-	plsql powershell prolog ps python python.2 r racket rexx rpython ruby rust scala scheme skew \
+	plsql powershell prolog ps python python.2 r racket rexx rpython ruby rust scala scheme skew sml \
 	swift swift3 swift4 swift5 tcl ts vala vb vhdl vimscript wasm wren yorick xslt zig
 
 step5_EXCLUDES += bash        # never completes at 10,000
@@ -173,6 +173,7 @@ rust_STEP_TO_PROG =          impls/rust/$($(1))
 scala_STEP_TO_PROG =         impls/scala/target/scala-2.11/classes/$($(1)).class
 scheme_STEP_TO_PROG =        $(scheme_STEP_TO_PROG_$(scheme_MODE))
 skew_STEP_TO_PROG =          impls/skew/$($(1)).js
+sml_STEP_TO_PROG =           impls/sml/$($(1))
 swift_STEP_TO_PROG =         impls/swift/$($(1))
 swift3_STEP_TO_PROG =        impls/swift3/$($(1))
 swift4_STEP_TO_PROG =        impls/swift4/$($(1))

impls/sml/Makefile

@@ -0,0 +1,13 @@
+STEPS = step0_repl.sml
+
+STEP_BINS = $(STEPS:%.sml=%)
+
+all: $(STEP_BINS)
+
+$(STEP_BINS): %: %.sml
+	mosmlc $< main.sml -o $@
+
+clean:
+	rm -f $(STEP_BINS) *.ui *.uo
+
+.PHONY: all clean

impls/sml/main.sml

@@ -0,0 +1 @@
+val _ = repl ()

impls/sml/run

@@ -0,0 +1,2 @@
+#!/bin/bash
+exec $(dirname $0)/${STEP:-stepA_mal} "${@}"

impls/sml/step0_repl.sml

@@ -0,0 +1,23 @@
+fun READ s: string =
+    s
+
+fun EVAL s: string =
+    s
+
+fun PRINT s: string =
+    s
+
+fun rep s: string =
+    (PRINT o EVAL o READ) s
+
+fun repl () =
+    let open TextIO
+    in (
+        print("user> ");
+        case inputLine(stdIn) of
+            SOME(line) => (
+                print(rep(line) ^ "\n");
+                repl ()
+            )
+            | NONE => ()
+    ) end