Revert "put extracted modules behind the switch, to enable doc generation"

This reverts commit 71bff7d2df.

lib/system.nim

@@ -2926,12 +2926,11 @@ proc compiles*(x: untyped): bool {.magic: "Compiles", noSideEffect, compileTime.
   discard
 
 
-when not defined(nimSlimSystem):
+import system/assertions
-  import system/assertions
+export assertions
-  export assertions
 
-  import system/iterators
+import system/iterators
-  export iterators
+export iterators
 
 
 proc find*[T, S](a: T, item: S): int {.inline.}=
@@ -3333,9 +3332,9 @@ template unlikely*(val: bool): bool =
     else:
       unlikelyProc(val)
 
-when not defined(nimSlimSystem):
+
-  import system/dollars
+import system/dollars
-  export dollars
+export dollars
 
 
 const
@@ -4346,10 +4345,10 @@ when defined(nimHasDefault):
   proc default*(T: typedesc): T {.magic: "Default", noSideEffect.}
     ## returns the default value of the type ``T``.
 
-when not defined(nimSlimSystem):
+import system/widestrs
-  import system/widestrs
+export widestrs
-  export widestrs
 
+when not defined(nimnoio):
   import system/io
   export io
 

lib/system/assertions.nim.cfg

@@ -1,2 +0,0 @@
---define:nimSlimSystem
-

lib/system/dollars.nim.cfg

@@ -1 +0,0 @@
---define:nimSlimSystem

lib/system/io.nim.cfg

@@ -1 +1 @@
---define:nimSlimSystem
+--define: nimnoio

lib/system/iterators.nim.cfg

@@ -1 +0,0 @@
---define:nimSlimSystem

lib/system/widestrs.nim.cfg

@@ -1 +0,0 @@
---define:nimSlimSystem