feat: Complete stream extraction

Also implements ++ string concatenation operator.

  Resolves #7, #18.

bin/extract_tests.xsh

@@ -13,6 +13,9 @@ DESTINATION = 'tests/extracted'
 # Extension for extracted files:
 EXT = 'fos'
 
+# Extension for desired input:
+INP = 'in'
+
 # Extension for expectations:
 EXP = 'expect'
 
@@ -34,6 +37,11 @@ for path in TEST_LIST:
     expath = destdir / f"{name}.{EXT}"
     expath.write_text(example)
     echo Wrote @(expath)
+    im = re.search(r'/\*\*\s+accepts.*?\n([\s\S]*?)\*\*/', details[em.end():])
+    if im:
+      ipath = destdir / f"{name}.{INP}"
+      ipath.write_text(im[1])
+      echo "  ...and" @(ipath)
     xm = re.search(r'/\*\*\s+writes.*?\n([\s\S]*?)\*\*/', details[em.end():])
     if xm:
       xpath = destdir / f"{name}.{EXP}"

bin/run_tests

@@ -9,8 +9,14 @@ diffed=0
 for dir in tests/extracted/*; do
   for file in $dir/*.$ext; do
     ((total++))
-    $command $file > $file.out
+    if [[ -f ${file%.*}.in ]]; then
-    if [[ $? -ne 0 ]]; then
+       cat ${file%.*}.in | $command $file > $file.out
+       result=$?
+    else
+       $command $file > $file.out
+       result=$?
+    fi
+    if [[ $result -ne 0 ]]; then
       echo ERROR: $command $file failed.
       ((failed++))
     else

mkdocs.yml

@@ -9,7 +9,7 @@ plugins:
 - search
 - semiliterate:
     ignore_folders: [target, lib]
-    exclude_extensions: ['.o', '.hi']
+    exclude_extensions: ['.o', '.hi', '.cmi', '.cmo']
     extract_standard_markdown:
       terminate: <!-- /md -->
 theme:

tests/basic.spt

@@ -293,7 +293,7 @@ test emit_several_default [[
                 >>>
 ]] parse succeeds
 /** writes
-3399677527121313*/
+3399677527121313**/
 
 /** md
 ### Streams are bidirectional
@@ -318,12 +318,13 @@ Kilroy
 **/
 /** writes
 What is your name?
-Hello, Kilroy**/
+Hello, Kilroy
+**/
 
 /** md
 ```
 
 queries users for their name and then writes a customized greeting. It also
-illustratesthe use of `++` for string concatenation, as opposed to `+` for
+illustrates the use of `++` for string concatenation, as opposed to `+` for
 (numerical) addition.
 **/

trans/haskell.str

@@ -23,6 +23,7 @@ rules
   import System.IO
   data IOStream = StdIO
 
+  -- Danger: These currently assume the stream is StdIO
   gets :: Show b => a -> b -> IO a
   gets s d = do
     putStr(show d)
@@ -33,6 +34,8 @@ rules
     putStr(d)
     return s
 
+  emit s = getLine
+
   main = do
     [<Preactions>()]return [val]]
 
@@ -41,6 +44,7 @@ rules
   hs: (_, LitString(x)) -> <haskLitString>x
   hs: (_, EscString(x)) -> x
   hs: (_, Sum(x, y))    -> $[([x] + [y])]
+  hs: (_, Concat(x, y)) -> $[([x] ++ [y])]
 
   hs: (Gets(_, xn), Gets(s, x)) -> v
     with v := <newname>"_fostr_get"
@@ -52,6 +56,10 @@ rules
   hs_gets: (s, xn, x ) -> $[[s] [<hs_getOp>xn] [x]]
   hs_getOp = get-type; (?STRING() < !"`getsStr`" + !"`gets`")
 
+  hs: (_, Emits(s)) -> v
+    with v := <newname>"_fostr_emitted"
+       ; <add-preactions>[$[[v] <- emit [s]]]
+
   hs: (_, Terminate(x)) -> $[[x];;]
   hs: (_, Sequence(l))  -> <last>l
   /* One drawback of using paramorphism is we have to handle lists

trans/javascript.str

@@ -3,24 +3,41 @@ imports libstrategolib signatures/- util
 
 rules
   js: TopLevel(x) -> $[// Fostr preamble
+  const _fostr_readline = require('readline');
+  const _fostr_events = require('events');
+  const _fostr_rl = _fostr_readline.createInterface({input: process.stdin});
   const Stdio = {
-    gets: v => { process.stdout.write(String(v)); return Stdio; },
+    gets:  v => { process.stdout.write(String(v)); return Stdio; },
+    emit: async () => {
+            const [line] = await _fostr_events.once(_fostr_rl, 'line');
+            return line + "\n"; }
   }
   function to(data, strm) {
     strm.gets(data);
     return data;
   }
+
+  const _fostr_body = async () => {
   // End of preamble
 
-  [x]]
+    [x]
+
+  // Fostr coda
+    _fostr_rl.close()
+  }
+  _fostr_body();
+  ]
+    with line := "[line]"
 
   js: Stream()     -> $[Stdio]
   js: Int(x)       -> x
   js: LitString(x) -> <javaLitString>x
   js: EscString(x) -> x
-  js: Sum(x,y)     -> $[[x] + [y]]
+  js: Sum(x, y)    -> $[[x] + [y]]
+  js: Concat(x, y) -> $[[x] + [y]]
   js: Gets(x, y)   -> $[[x].gets([y])]
   js: To(x, y)     -> $[to([x],[y])]
+  js: Emits(x)     -> $[(await [x].emit())]
   js: Terminate(x) -> x
   js: Sequence(l)  -> <join(|";\n")>l
 

trans/ocaml.str

@@ -12,9 +12,10 @@ imports libstrategolib signatures/- util signature/TYPE analysis
 
 rules
   ml: (_, TopLevel(x)) -> $[(* fostr preamble *)
-  type stream = { getS: string -> stream }
+  type stream = { getS: string -> stream; emitS: unit -> string }
   let rec stdio = {
-    getS = (fun s -> print_string s; stdio)
+    getS = (fun s -> print_string s; stdio);
+    emitS = (fun () -> (read_line ()) ^ "\n");
   };;
   (* End of preamble *)
 
@@ -24,11 +25,15 @@ rules
   ml: (_, Int(x))       -> x
   ml: (_, LitString(x)) -> $[{|[<un-single-quote>x]|}]
   ml: (_, EscString(x)) -> x
-  ml: (_, Sum(x,y))     -> $[[x] + [y]]
+  ml: (_, Sum(x, y))    -> $[[x] + [y]]
+  ml: (_, Concat(x, y)) -> $[[x] ^ [y]]
+
   ml: (Gets(_,yn), Gets(x, y))
     -> $[([x]).getS ([<ml_str>(yn,y)])]
   ml: (To(xn,_),   To(x, y))
     -> $[let _fto = ([x]) in (ignore (([y]).getS ([<ml_str>(xn,"_fto")])); _fto)]
+  ml: (_, Emits(s))     -> $[[s].emitS ()]
+
   ml: (_, Terminate(x)) -> x
   ml: (_, Sequence(l))  -> <ml_seq>l
   

trans/python.str

@@ -9,7 +9,7 @@ rules
       print(v, file=sys.stdout, end='')
       return self
     def emit(self):
-      return input()
+      return input() + "\n" # Python inconsistently strips when using input
   def to(data,strm):
     strm.gets(data)
     return data