bugfix: echo vs debugEcho

compiler/semexprs.nim

@@ -686,6 +686,9 @@ proc semEcho(c: PContext, n: PNode): PNode =
   for i in countup(1, sonsLen(n) - 1): 
     var arg = semExprWithType(c, n.sons[i])
     n.sons[i] = semExpr(c, buildStringify(c, arg))
+  
+  let t = n.sons[0].typ
+  if tfNoSideEffect notin t.flags: incl(c.p.owner.flags, sfSideEffect)
   result = n
   
 proc buildEchoStmt(c: PContext, n: PNode): PNode = 

compiler/sempass2.nim

@@ -7,7 +7,8 @@
 #    distribution, for details about the copyright.
 #
 
-#  included from sem.nim
+import
+  ast, astalgo, msgs, semdata
 
 # Second semantic checking pass over the AST. Necessary because the old
 # way had some inherent problems. Performs:
@@ -15,9 +16,25 @@
 # * procvar checks
 # * effect tracking
 # * closure analysis
-# * checks for invalid usages of compiletime magics
+# * checks for invalid usages of compiletime magics (not implemented)
-# * checks for invalid usages of PNimNode
+# * checks for invalid usages of PNimNode (not implemented)
 # * later: will do an escape analysis for closures at least
 
-proc sem2(c: PContext, n: PNode): PNode =
+# Predefined effects:
-  nil
+#   io, time (time dependent), gc (performs GC'ed allocation), exceptions,
+#   side effect (accesses global), store (stores into *type*),
+#   store_unkown (performs some store) --> store(any)|store(x) 
+#   load (loads from *type*), recursive (recursive call),
+#   endless (has endless loops), --> user effects are defined over *patterns*
+#   --> a TR macro can annotate the proc with user defined annotations
+#   --> the effect system can access these
+
+proc sem2call(c: PContext, n: PNode): PNode =
+  assert n.kind in nkCallKinds
+  
+  
+
+proc sem2sym(c: PContext, n: PNode): PNode =
+  assert n.kind == nkSym
+  
+

doc/manual.txt

@@ -3431,7 +3431,7 @@ or ``ref T`` or ``ptr T`` this means no locations are modified. It is a static
 error to mark a proc/iterator to have no side effect if the compiler cannot
 verify this.
 
-As a special semantic rule, the built-in ``echo`` pretends to be free of 
+As a special semantic rule, the built-in ``debugEcho`` pretends to be free of 
 side effects, so that it can be used for debugging routines marked as
 ``noSideEffect``.