Initial test for slow, minimal LISP - DRAWL

src/toolsrc/drawl.pla

@@ -0,0 +1,67 @@
+include "inc/cmdsys.plh"
+
+word readline
+
+def num_parse(instr)
+  while ^instr >= '0' and ^instr <= '9'
+    putc(^instr)
+    instr++
+  loop
+  return instr
+end
+
+def sym_parse(instr)
+  while ^instr > ')' and toupper(^instr) <= 'Z'
+    putc(toupper(^instr))
+    instr++
+  loop
+  return instr
+end
+
+def exp_parse(instr)
+  while ^instr
+    when ^instr
+      is '!'
+        return 0
+      is ' '
+        instr++
+        break
+      is '('
+        putln
+        instr = exp_parse(instr + 1)
+        break
+      is ')'
+        putln
+        return instr + 1
+      is '0'
+      is '1'
+      is '2'
+      is '3'
+      is '4'
+      is '5'
+      is '6'
+      is '7'
+      is '8'
+      is '9'
+        putc('.')
+        instr = num_parse(instr)
+        break
+      otherwise
+        if  ^instr > ')' and toupper(^instr) <= 'Z'
+          putc('.')
+          instr = sym_parse(instr)
+        else
+          putc('\\')
+          putc(^instr)
+          instr++
+        fin
+    wend
+  loop
+  return instr
+end
+
+repeat
+  readline = gets('?'|$80)
+  ^(readline + ^readline + 1) = 0
+until not exp_parse(readline + 1)
+done