PS: add stepA_more.

Sync other steps. In particular, self reference in function definition
and putting readline into _readline function.

15 files changed, 481 insertions, 118 deletions

diff --git a/docs/TODO b/docs/TODO
index a260cc8..324484e 100644
--- a/docs/TODO
+++ b/docs/TODO
@@ -13,13 +13,14 @@ All:
     - support metadata on symbol, hash-map, list, vector, function, atom
     - regular expression matching in runtest
 
-    - unindent tco while loop for step5-A
     - Print full exception when test gets EOF from expect
     - Note that bash 4, Java 1.7, php 5.3 required
     - Break out language eval into step0.5
-    - use str instead of slurp-do
 
-    - move interop to step6 and use interop for slurp?
+    - unindent tco while loop for step5-A
+    - use str instead of slurp-do
+    - move printing from type to printer
+    - fix conj list vs. vector behavior
 
 ---------------------------------------------
 
@@ -54,7 +55,7 @@ Java:
 Postscript:
     - negative numbers
     - quotes/backslashes in strings
-    - step 7-A
+    - vectors, hash-maps, metadata, atoms
 
 Rust:
     - http://www.rustforrubyists.com/book/index.html
diff --git a/docs/step_notes.txt b/docs/step_notes.txt
index 4947edf..63e7a76 100644
--- a/docs/step_notes.txt
+++ b/docs/step_notes.txt
@@ -161,11 +161,14 @@ Step Notes:
         - add 'defmacro!' and 'macroexpand'
         - store ismacro property on function metadata
 
+- step9_interop
+
 - stepA_more
     - types module:
         - throw function
-        - map, apply functions
-        - symbol?, nil?, true?, false?
+        - apply, map functions: should not directly call EVAL, which
+          requires the function object to be runnable
+        - symbol?, nil?, true?, false?, sequential? (if not already)
         - conj, first, rest
     - EVAL:
         - try*/catch*: for normal exceptions, extracts string
diff --git a/ps/reader.ps b/ps/reader.ps
index e524d4c..dba2a4a 100644
--- a/ps/reader.ps
+++ b/ps/reader.ps
@@ -184,9 +184,13 @@
         (unexpected '[') throw
     }{ ch 93 eq { %elseif ']'
         (unexpected ']') throw
+    }{ ch 123 eq { %elseif '{'
+        (unexpected '{') throw
+    }{ ch 125 eq { %elseif '}'
+        (unexpected '}') throw
     }{ % else
         str idx read_atom
-    } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
+    } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
 
     % return: ast string new_idx
 end } def
diff --git a/ps/step0_repl.ps b/ps/step0_repl.ps
index 9dbf107..046e5a1 100644
--- a/ps/step0_repl.ps
+++ b/ps/step0_repl.ps
@@ -1,4 +1,6 @@
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     % just "return" the input string
     /str exch def
@@ -26,17 +28,10 @@
 % repl
 /REP { READ (stub env) EVAL PRINT } def
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     REP print (\n) print
 } bind loop
 
diff --git a/ps/step1_read_print.ps b/ps/step1_read_print.ps
index bc87226..aa2ce25 100644
--- a/ps/step1_read_print.ps
+++ b/ps/step1_read_print.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -26,23 +28,19 @@ end } def
 % repl
 /REP { READ (stub env) EVAL PRINT } def
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
         (Error: ) print
         get_error_data false _pr_str print (\n) print
+        $error /newerror false put
+        $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step2_eval.ps b/ps/step2_eval.ps
index aa34bf5..b353f8e 100644
--- a/ps/step2_eval.ps
+++ b/ps/step2_eval.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -39,7 +41,8 @@ end } def
         ast env eval_ast
     }{ %else apply the list
         /el ast env eval_ast def
-        el _rest el _first exec % apply function to args
+        el _rest el _first % stack: ast function
+        exec % apply function to args
     } ifelse
 end } def
 
@@ -60,23 +63,19 @@ end } def
 
 /REP { READ repl_env EVAL PRINT } def
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
         (Error: ) print
         get_error_data false _pr_str print (\n) print
+        $error /newerror false put
+        $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step3_env.ps b/ps/step3_env.ps
index e906386..a86e036 100644
--- a/ps/step3_env.ps
+++ b/ps/step3_env.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -29,7 +31,8 @@ end } def
 /EVAL { 8 dict begin
     /env exch def
     /ast exch def
-    %(EVAL: ) print ast ==
+
+    %(EVAL: ) print ast true _pr_str print (\n) print
     ast _list? not { %if not a list
         ast env eval_ast
     }{ %else apply the list
@@ -53,7 +56,8 @@ end } def
             a2 let_env EVAL
         }{
             /el ast env eval_ast def
-            el _rest el _first exec % apply function to args
+            el _rest el _first % stack: ast function
+            exec % apply function to args
         } ifelse } ifelse
     } ifelse
 end } def
@@ -76,23 +80,19 @@ end } def
 (*) { dup 0 get exch 1 get mul } _ref
 (/) { dup 0 get exch 1 get idiv } _ref
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
         (Error: ) print
         get_error_data false _pr_str print (\n) print
+        $error /newerror false put
+        $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step4_if_fn_do.ps b/ps/step4_if_fn_do.ps
index 56152c6..11c475f 100644
--- a/ps/step4_if_fn_do.ps
+++ b/ps/step4_if_fn_do.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -77,18 +79,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 EVAL
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse
     } ifelse
@@ -112,17 +117,10 @@ types_ns { _ref } forall
 
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -131,6 +129,7 @@ types_ns { _ref } forall
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step5_tco.ps b/ps/step5_tco.ps
index 52e5d02..a501b06 100644
--- a/ps/step5_tco.ps
+++ b/ps/step5_tco.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -84,18 +86,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 /loop? true def
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse
     } ifelse
@@ -122,17 +127,10 @@ types_ns { _ref } forall
 
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -141,6 +139,7 @@ types_ns { _ref } forall
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step6_file.ps b/ps/step6_file.ps
index 2172942..b90bac5 100644
--- a/ps/step6_file.ps
+++ b/ps/step6_file.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -84,18 +86,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 /loop? true def
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse
     } ifelse
@@ -128,8 +133,6 @@ types_ns { _ref } forall
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 (\(def! load-file \(fn* \(f\) \(eval \(read-string \(str "\(do " \(slurp f\) "\)"\)\)\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 userdict /ARGUMENTS known { %if command line arguments
     ARGUMENTS length 0 gt { %if more than 0 arguments
         ARGUMENTS {
@@ -139,14 +142,9 @@ userdict /ARGUMENTS known { %if command line arguments
     } if
 } if
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -155,6 +153,7 @@ userdict /ARGUMENTS known { %if command line arguments
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step7_quote.ps b/ps/step7_quote.ps
index 17d7e00..9ca3eb5 100644
--- a/ps/step7_quote.ps
+++ b/ps/step7_quote.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -116,18 +118,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 /loop? true def
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
     } ifelse
@@ -160,8 +165,6 @@ types_ns { _ref } forall
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 (\(def! load-file \(fn* \(f\) \(eval \(read-string \(str "\(do " \(slurp f\) "\)"\)\)\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 userdict /ARGUMENTS known { %if command line arguments
     ARGUMENTS length 0 gt { %if more than 0 arguments
         ARGUMENTS {
@@ -171,14 +174,9 @@ userdict /ARGUMENTS known { %if command line arguments
     } if
 } if
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -187,6 +185,7 @@ userdict /ARGUMENTS known { %if command line arguments
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step8_macros.ps b/ps/step8_macros.ps
index 1af1829..cfce140 100644
--- a/ps/step8_macros.ps
+++ b/ps/step8_macros.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -158,18 +160,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 /loop? true def
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
       } ifelse
@@ -199,14 +204,10 @@ types_ns { _ref } forall
 (eval) { 0 get repl_env EVAL } _ref
 /slurp { (r) file dup bytesavailable string readstring pop } def
 (slurp) { 0 get slurp } _ref
-(pstack) { (vvv\n) print pstack (^^^\n) print } _ref
-(p1) { 1 index true _pr_str print (\n) print } _ref
 
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 (\(def! load-file \(fn* \(f\) \(eval \(read-string \(str "\(do " \(slurp f\) "\)"\)\)\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 userdict /ARGUMENTS known { %if command line arguments
     ARGUMENTS length 0 gt { %if more than 0 arguments
         ARGUMENTS {
@@ -216,14 +217,9 @@ userdict /ARGUMENTS known { %if command line arguments
     } if
 } if
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -232,6 +228,7 @@ userdict /ARGUMENTS known { %if command line arguments
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/step9_interop.ps b/ps/step9_interop.ps
index 5ccadf5..743422b 100644
--- a/ps/step9_interop.ps
+++ b/ps/step9_interop.ps
@@ -2,6 +2,8 @@
 (reader.ps) run
 
 % read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
 /READ {
     /str exch def
     str read_str
@@ -172,18 +174,21 @@ end } def
                 /params null % close over parameters
                 /ast null    % close over ast
                 /env null    % close over environment
+                /data { __self__ fload EVAL }
             >>
             dup length dict copy % make an actual copy/new instance
             dup /params a1 put  % insert closed over a1 into position 2
             dup /ast a2 put  % insert closed over a2 into position 3
             dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
         }{
             /el ast env eval_ast def
-            el _first _mal_function? { % if user defined function
-                el _rest el _first fload % stack: ast new_env
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
                 /loop? true def
             }{ %else (regular procedure/function)
-                el _rest el _first exec % apply function to args
+                exec % apply function to args
             } ifelse
         } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
       } ifelse
@@ -213,14 +218,10 @@ types_ns { _ref } forall
 (eval) { 0 get repl_env EVAL } _ref
 /slurp { (r) file dup bytesavailable string readstring pop } def
 (slurp) { 0 get slurp } _ref
-(pstack) { (vvv\n) print pstack (^^^\n) print } _ref
-(p1) { 1 index true _pr_str print (\n) print } _ref
 
 (\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
 (\(def! load-file \(fn* \(f\) \(eval \(read-string \(str "\(do " \(slurp f\) "\)"\)\)\)\)\)) RE pop
 
-/stdin (%stdin) (r) file def 
-
 userdict /ARGUMENTS known { %if command line arguments
     ARGUMENTS length 0 gt { %if more than 0 arguments
         ARGUMENTS {
@@ -230,14 +231,9 @@ userdict /ARGUMENTS known { %if command line arguments
     } if
 } if
 { % loop
-    (user> ) print flush
-
-    stdin 99 string readline
-
+    (user> ) _readline
     not { exit } if  % exit if EOF
 
-    %(\ngot line: ) print dup print (\n) print flush
-
     { %try
         REP print (\n) print
     } stopped {
@@ -246,6 +242,7 @@ userdict /ARGUMENTS known { %if command line arguments
         $error /newerror false put
         $error /errorinfo null put
         clear
+        cleardictstack
     } if
 } bind loop
 
diff --git a/ps/stepA_more.ps b/ps/stepA_more.ps
new file mode 100644
index 0000000..66494cc
--- /dev/null
+++ b/ps/stepA_more.ps
@@ -0,0 +1,295 @@
+(types.ps) run
+(reader.ps) run
+
+% read
+/_readline { print flush (%stdin) (r) file 99 string readline } def
+
+/READ {
+    /str exch def
+    str read_str
+} def
+
+
+% eval
+% is_pair?: ast -> is_pair? -> bool
+% return true if non-empty list, otherwise false
+/is_pair? { 
+    dup _list? { length 0 gt }{ pop false } ifelse
+} def
+
+% ast -> quasiquote -> new_ast
+/quasiquote { 3 dict begin
+    /ast exch def
+    ast is_pair? not { %if not is_pair?
+        /quote ast 2 _list
+    }{ 
+        /a0 ast 0 get def
+        a0 /unquote eq { %if a0 unquote symbol
+            ast 1 get
+        }{ a0 is_pair? { %elseif a0 is_pair?
+            /a00 a0 0 get def
+            a00 /splice-unquote eq { %if splice-unquote
+                /concat a0 1 get ast _rest quasiquote 3 _list
+            }{ %else not splice-unquote
+                /cons a0 quasiquote ast _rest quasiquote 3 _list
+            } ifelse
+        }{ % else not a0 is_pair?
+            /cons a0 quasiquote ast _rest quasiquote 3 _list
+        } ifelse } ifelse
+    } ifelse
+end } def
+
+/is_macro_call? { 3 dict begin
+    /env exch def
+    /ast exch def
+    ast _list? {
+        /a0 ast 0 get def
+        a0 _symbol? { %if a0 is symbol
+            env a0 env_find null ne { %if a0 is in env
+                env a0 env_get _mal_function? { %if user defined function
+                    env a0 env_get /macro? get true eq %if marked as macro
+                }{ false } ifelse
+            }{ false } ifelse
+        }{ false } ifelse
+    }{ false } ifelse
+end } def
+
+/macroexpand { 3 dict begin
+    /env exch def
+    /ast exch def
+    {
+        ast env is_macro_call? {
+            /mac env   ast 0 get   env_get def
+            /ast ast _rest mac fload EVAL def
+        }{
+            exit
+        } ifelse
+    } loop 
+    ast
+end } def
+
+/eval_ast { 2 dict begin
+    /env exch def
+    /ast exch def
+    %(eval_ast: ) print ast ==
+    ast _symbol? { %if symbol
+        env ast env_get
+    }{ ast _list? { %elseif list
+        [
+            ast {
+                env EVAL
+            } forall
+        ]
+    }{ % else
+        ast
+    } ifelse } ifelse
+end } def
+
+/EVAL { 13 dict begin
+    { %loop (TCO) 
+
+    /env exch def
+    /ast exch def
+    /loop? false def
+
+    %(EVAL: ) print ast true _pr_str print (\n) print
+    ast _list? not { %if not a list
+        ast env eval_ast
+    }{ %else apply the list
+      /ast ast env macroexpand def
+      ast _list? not { %if no longer a list
+          ast
+      }{ %else still a list
+        /a0 ast 0 get def
+        /def! a0 eq { %if def!
+            /a1 ast 1 get def
+            /a2 ast 2 get def
+            env a1  a2 env EVAL  env_set
+        }{ /let* a0 eq { %if let*
+            /a1 ast 1 get def
+            /a2 ast 2 get def
+            /let_env env [ ] [ ] env_new def
+            0 2 a1 length 1 sub { %for each pair
+                /idx exch def
+                let_env
+                    a1 idx get
+                    a1 idx 1 add get let_env EVAL
+                    env_set
+                    pop % discard the return value
+            } for
+            a2 let_env EVAL
+        }{ /quote a0 eq { %if quote
+            ast 1 get
+        }{ /quasiquote a0 eq { %if quasiquote
+            ast 1 get quasiquote   env EVAL
+        }{ /defmacro! a0 eq { %if defmacro!
+            /a1 ast 1 get def
+            /a2 ast 2 get def
+            a2 env EVAL
+            dup /macro? true put % set macro flag
+            env exch a1 exch env_set % def! it
+        }{ /macroexpand a0 eq { %if defmacro!
+            ast 1 get env macroexpand
+        }{ /ps* a0 eq { %if ps*
+            count /stackcnt exch def
+            ast 1 get
+            {
+                token not { exit } if
+                exch
+            } loop
+            exec
+            count stackcnt gt { % if new operands on stack
+                % return an list of new operands
+                count stackcnt sub array astore
+            }{
+                null % return nil
+            } ifelse
+        }{ /do a0 eq { %if do
+            ast length 2 gt { %if ast has more than 2 elements
+                ast 1 ast length 2 sub getinterval env eval_ast pop
+            } if
+            ast ast length 1 sub get % last ast becomes new ast
+            env
+            /loop? true def % loop
+        }{ /try* a0 eq { %if try*
+            { %try
+                countdictstack /dictcnt exch def
+                count /stackcnt exch def
+                %(here1:\n) print pstack
+                ast 1 get env EVAL
+                %(here2\n) print
+            } stopped { %catch
+                %(here3:\n) print pstack
+                % clean up the dictionary stack
+                1 1 countdictstack dictcnt sub { %foreach added dict
+                    %(popping dict\n) print
+                    pop end % pop idx and pop dict
+                    %(new ast: ) print ast true _pr_str print (\n) print
+                } for
+                % clean up the operand stack
+                %(op stack cleanup: ) print count stackcnt sub ==
+                count 1 exch 1 exch stackcnt sub { %foreach added operand
+                    %(op stack: ) print pstack
+                    pop pop % pop idx and operand
+                    %(popped op stack\n) print pstack
+                } for
+                % get error data and reset $error dict
+                /errdata get_error_data def
+                $error /newerror false put
+                $error /errorinfo null put
+
+                ast length 3 lt { %if no third (catch*) form
+                    errdata throw
+                } if
+                %(here4: ) print ast true _pr_str print (\n) print
+                ast 2 get 0 get (catch*) eq not { %if third form not catch*
+                    (No catch* in throw form) throw
+                } if
+                %(here5: ) print ast 2 get 2 get true _pr_str print (\n) print
+                ast 2 get 2 get
+                %(here5: ) print ast 2 get 1 get true _pr_str print (\n) print
+                %(here6: ) print errdata true _pr_str print (\n) print
+                env [ ast 2 get 1 get ] [ errdata ] env_new
+                %(here7:\n) print pstack
+                EVAL
+            } if
+        }{ /if a0 eq { %if if
+            /a1 ast 1 get def
+            /cond a1 env EVAL def
+            cond null eq cond false eq or { % if cond is nil or false
+                ast length 3 gt { %if false branch with a3
+                    ast 3 get env
+                    /loop? true def
+                }{ % else false branch with no a3
+                    null
+                } ifelse
+            }{ % true branch
+                ast 2 get env
+                /loop? true def
+            } ifelse
+        }{ /fn* a0 eq { %if fn*
+            /a1 ast 1 get def
+            /a2 ast 2 get def
+            <<
+                /type /_maltype_function % user defined function
+                /macro? false % macro flag, false by default
+                /params null % close over parameters
+                /ast null    % close over ast
+                /env null    % close over environment
+                /data { __self__ fload EVAL }
+            >>
+            dup length dict copy % make an actual copy/new instance
+            dup /params a1 put  % insert closed over a1 into position 2
+            dup /ast a2 put  % insert closed over a2 into position 3
+            dup /env env put % insert closed over env into position 4
+            dup   dup /data get   exch 0 exch put % insert self reference
+        }{
+            /el ast env eval_ast def
+            el _rest el _first % stack: ast function
+            dup _mal_function? { % if user defined function
+                fload % stack: ast new_env
+                /loop? true def
+            }{ %else (regular procedure/function)
+                exec % apply function to args
+            } ifelse
+        } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse } ifelse
+      } ifelse
+    } ifelse
+
+    loop? not { exit } if
+    } loop % TCO
+end } def
+
+
+% print
+/PRINT {
+    true _pr_str
+} def
+
+
+% repl
+/repl_env null [ ] [ ] env_new def
+
+/RE { READ repl_env EVAL } def
+/REP { READ repl_env EVAL PRINT } def
+/_ref { repl_env 3 1 roll env_set pop } def
+
+types_ns { _ref } forall
+
+(readline) { 0 get _readline not { null } if } _ref
+(read-string) { 0 get read_str } _ref
+(eval) { 0 get repl_env EVAL } _ref
+/slurp { (r) file dup bytesavailable string readstring pop } def
+(slurp) { 0 get slurp } _ref
+
+(\(def! not \(fn* \(a\) \(if a false true\)\)\)) RE pop
+(\(defmacro! cond \(fn* \(& xs\) \(if \(> \(count xs\) 0\) \(list 'if \(first xs\) \(if \(> \(count xs\) 1\) \(nth xs 1\) \(throw "odd number of forms to cond"\)\) \(cons 'cond \(rest \(rest xs\)\)\)\)\)\)\)) RE pop
+(\(defmacro! or \(fn* \(& xs\) \(if \(empty? xs\) nil \(if \(= 1 \(count xs\)\) \(first xs\) `\(let* \(or_FIXME ~\(first xs\)\) \(if or_FIXME or_FIXME \(or ~@\(rest xs\)\)\)\)\)\)\)\)) RE pop
+(\(def! load-file \(fn* \(f\) \(eval \(read-string \(str "\(do " \(slurp f\) "\)"\)\)\)\)\)) RE pop
+
+userdict /ARGUMENTS known { %if command line arguments
+    ARGUMENTS length 0 gt { %if more than 0 arguments
+        ARGUMENTS {
+            (\(load-file ") exch ("\)) concatenate concatenate RE pop
+        } forall
+        quit
+    } if
+} if
+{ % loop
+    (user> ) _readline
+    not { exit } if  % exit if EOF
+
+    { %try
+        REP print (\n) print
+    } stopped {
+        (Error: ) print
+        get_error_data false _pr_str print (\n) print
+        $error /newerror false put
+        $error /errorinfo null put
+        clear
+        cleardictstack
+    } if
+} bind loop
+
+(\n) print  % final newline before exit for cleanliness
+quit
diff --git a/ps/types.ps b/ps/types.ps
index 1eb2cf5..30019b9 100644
--- a/ps/types.ps
+++ b/ps/types.ps
@@ -7,7 +7,7 @@
 /concatenate { %def
     dup type 2 index type 2 copy ne { %if
         pop pop
-        errordict begin (concatentate) typecheck end
+        errordict begin (concatenate) typecheck end
     }{ %else
         /stringtype ne exch /arraytype ne and {
             errordict begin (concatenate) typecheck end
@@ -120,6 +120,11 @@ end } def
     } ifelse
 end } def
 
+/_nil? { null eq } def
+/_true? { true eq } def
+/_false? { false eq } def
+
+
 %
 % Symbols
 %
@@ -147,6 +152,10 @@ end } def
     env_new                  % stack: ast new_env
 } def
 
+% function_or_block -> callable -> block
+% if this is a user defined mal function, get its executable block
+/callable { dup _mal_function? { /data get } if } def
+
 %
 % Errors/Exceptions
 %
@@ -199,8 +208,6 @@ end } def
 /_list? {
     dup xcheck not exch type /arraytype eq and
 } def
-/_first { 0 get } def
-/_rest { dup length 1 sub 1 exch getinterval } def
 /_nth { get } def
 
 /_cons {
@@ -211,10 +218,72 @@ end } def
     dup 1 lst putinterval % rest of the elements
 } def
 
-/_concat {
-    concatenate
+/concat { % replaces matric concat
+    dup length 0 eq { %if just concat
+        0 _list
+    }{ dup length 1 eq { %elseif concat of single item
+        0 get % noop
+    }{ % else
+        [] exch
+        {
+            concatenate
+        } forall
+    } ifelse } ifelse
+} def
+
+%
+% Sequence operations
+%
+/_first {
+    dup length 0 gt { 0 get }{ pop null } ifelse
+} def
+/_rest {
+    dup length 0 gt {
+        dup length 1 sub 1 exch getinterval
+    }{
+        pop 0 array
+    } ifelse
 } def
 
+% [function args... arg_list] -> apply -> result
+/apply { 1 dict begin
+    /args exch def
+    args 0 get callable % make sure function is callable
+    args 1 args length 2 sub getinterval
+    args args length 1 sub get
+    concatenate args 0 get % stack: args function
+    exec
+end } def
+
+% function list -> _map -> new_list
+/_map { 1 dict begin
+    /args exch def
+    callable % make sure function is callable
+    %/new_list args length array def
+    args {
+        1 array astore
+        exch dup 3 1 roll % stack: fn arg fn
+        exec exch % stack: result fn
+    } forall 
+    pop % remove the function
+    args length array astore
+end } def
+
+/_sequential? { _list? } def
+
+/conj { 5 dict begin
+    /args exch def
+    /src_list args 0 get def
+    /new_len src_list length   args length 1 sub   add def
+    /new_list new_len array def
+    new_list   new_len src_list length sub   src_list putinterval
+    args length 1 sub -1 1 {
+        /idx exch def
+        new_list   args length idx sub 1 sub   args idx get   put
+    } for
+    new_list
+end } def
+
 
 %
 % Env implementation
@@ -286,6 +355,10 @@ end } def
     (prn)     { ( ) true _pr_str_args print (\n) print null }
     (println) { () false _pr_str_args print (\n) print null }
     (=)       { dup 0 get exch 1 get _equal? }
+    (symbol?) { 0 get _symbol? }
+    (nil?)    { 0 get _nil? }
+    (true?)   { 0 get _true? }
+    (false?)  { 0 get _false? }
     (<)       { dup 0 get exch 1 get lt }
     (<=)      { dup 0 get exch 1 get le }
     (>)       { dup 0 get exch 1 get gt }
@@ -294,13 +367,18 @@ end } def
     (-)       { dup 0 get exch 1 get sub }
     (*)       { dup 0 get exch 1 get mul }
     (/)       { dup 0 get exch 1 get idiv }
+    (throw)   { 0 get throw }
     (list)    { dup pop } % noop
     (list?)   { 0 get _list? }
     (cons)    { dup 0 get exch 1 get _cons }
-    (concat)  { dup 0 get exch 1 get _concat }
+    (concat)  { concat }
+    (sequential?) { 0 get _sequential? }
     (empty?)  { 0 get length 0 eq }
     (count)   { 0 get length }
     (nth)     { dup 0 get exch 1 get _nth }
     (first)   { 0 get _first }
     (rest)    { 0 get _rest }
+    (apply)   { apply }
+    (map)     { dup 0 get exch 1 get _map }
+    (conj)    { conj }
 >> def