Interactive Executive

extra/shell/parser/parser.factor

@@ -0,0 +1,73 @@
+
+USING: kernel arrays strings sequences sequences.deep peg peg.ebnf ;
+
+IN: shell.parser
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+TUPLE: incantation command stdin stdout background ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+TUPLE: single-quoted-expr expr ;
+TUPLE: double-quoted-expr expr ;
+TUPLE: back-quoted-expr   expr ;
+TUPLE: glob-expr          expr ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: <single-quoted-expr> single-quoted-expr boa ;
+: <double-quoted-expr> double-quoted-expr boa ;
+: <back-quoted-expr>   back-quoted-expr boa ;
+: <glob-expr>          glob-expr boa ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+EBNF: expr
+
+space = " "
+
+tab   = "\t"
+
+white = (space | tab)
+
+whitespace = (white)* => [[ drop ignore ]]
+
+squote        = "'"
+
+single-quoted = squote (!(squote) .)* squote => [[ second >string <single-quoted-expr> ]]
+
+dquote        = '"'
+
+double-quoted = dquote (!(dquote) .)* dquote => [[ second >string <double-quoted-expr> ]]
+
+bquote = "`"
+
+back-quoted = bquote (!(bquote) .)* bquote => [[ second >string <back-quoted-expr> ]]
+
+glob-char = ("*" | "?")
+
+non-glob-char = !(glob-char | white) .
+
+glob-beginning-string = (non-glob-char)* [[ >string ]]
+
+glob-rest-string = (non-glob-char)+ [[ >string ]]
+
+glob = glob-beginning-string glob-char (glob-rest-string | glob-char)* => [[ flatten concat <glob-expr> ]]
+
+other = (!(white | "&" | ">" | ">>" | "<") .)+ => [[ >string ]]
+
+element = (single-quoted | double-quoted | back-quoted | glob | other)
+
+to-file = ">" whitespace other => [[ second ]]
+
+in-file = "<" whitespace other => [[ second ]]
+
+ap-file = ">>" whitespace other  => [[ second ]]
+
+redirection = (in-file)? whitespace (to-file | ap-file)?
+
+line = (element whitespace)+ (in-file)? whitespace (to-file | ap-file)? whitespace ("&")? => [[ first4 incantation boa ]]
+
+;EBNF
+

extra/shell/shell.factor

@@ -0,0 +1,88 @@
+
+USING: kernel words continuations namespaces debugger sequences combinators
+       io io.files io.launcher
+       accessors multi-methods newfx shell.parser ;
+
+IN: shell
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: cd ( args -- )
+  dup empty?
+    [ drop home set-current-directory ]
+    [ first     set-current-directory ]
+  if ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: pwd ( args -- )
+  drop
+  current-directory get
+  print ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: swords ( -- seq ) { "cd" "pwd" } ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+GENERIC: expand ( expr -- expr )
+
+METHOD: expand { single-quoted-expr } expr>> ;
+
+METHOD: expand { double-quoted-expr } expr>> ;
+
+METHOD: expand { object } ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: expansion ( command -- command ) [ expand ] map ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: run-incantation ( incantation -- )
+  <process>
+    over command>> expansion >>command
+    over stdin>>             >>stdin
+    over stdout>>            >>stdout
+  swap background>>
+    [ run-detached drop ]
+    [ [ try-process ] [ print-error drop ] recover ]
+  if ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: chant ( incantation -- )
+    dup command>> first swords member-of?
+      [ command>> unclip "shell" lookup execute ]
+      [ run-incantation ]
+    if ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: prompt ( -- )
+  current-directory get write
+  " $ " write
+  flush ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: shell ( -- )
+  prompt
+  readln
+    {
+      { [ dup f = ] [ drop ] }
+      { [ dup "exit" = ] [ drop ] }
+      { [ dup "" = ] [ drop shell ] }
+      { [ dup expr ] [ expr ast>> chant shell ] }
+      { [ t ]        [ drop shell ] }
+    }
+  cond ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: ix ( -- ) shell ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+MAIN: ix