prepare for the enforcement of std prefix (#22873)

follow up https://github.com/nim-lang/Nim/pull/22851

compiler/aliases.nim

@@ -10,7 +10,9 @@
 ## Simple alias analysis for the HLO and the code generators.
 
 import
-  ast, astalgo, types, trees, intsets
+  ast, astalgo, types, trees
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/ast.nim

@@ -10,8 +10,10 @@
 # abstract syntax tree + symbol table
 
 import
-  lineinfos, hashes, options, ropes, idents, int128, tables, wordrecg
-from strutils import toLowerAscii
+  lineinfos, options, ropes, idents, int128, wordrecg
+
+import std/[tables, hashes]
+from std/strutils import toLowerAscii
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/astalgo.nim

@@ -12,10 +12,11 @@
 # the data structures here are used in various places of the compiler.
 
 import
-  ast, hashes, intsets, options, lineinfos, ropes, idents, rodutils,
+  ast, options, lineinfos, ropes, idents, rodutils,
   msgs
 
-import strutils except addf
+import std/[hashes, intsets]
+import std/strutils except addf
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -408,7 +409,7 @@ proc symToYaml(conf: ConfigRef; n: PSym, indent: int = 0, maxRecDepth: int = - 1
   var marker = initIntSet()
   result = symToYamlAux(conf, n, marker, indent, maxRecDepth)
 
-import tables
+import std/tables
 
 const backrefStyle = "\e[90m"
 const enumStyle = "\e[34m"

compiler/ccgtypes.nim

@@ -11,7 +11,7 @@
 
 # ------------------------- Name Mangling --------------------------------
 
-import sighashes, modulegraphs, strscans
+import sighashes, modulegraphs, std/strscans
 import ../dist/checksums/src/checksums/md5
 
 type

compiler/ccgutils.nim

@@ -10,9 +10,11 @@
 # This module declares some helpers for the C code generator.
 
 import
-  ast, types, hashes, strutils, msgs, wordrecg,
+  ast, types, msgs, wordrecg,
   platform, trees, options, cgendata
 
+import std/[hashes, strutils]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/cgen.nim

@@ -10,11 +10,11 @@
 ## This module implements the C code generator.
 
 import
-  ast, astalgo, hashes, trees, platform, magicsys, extccomp, options, intsets,
+  ast, astalgo, trees, platform, magicsys, extccomp, options,
   nversion, nimsets, msgs, bitsets, idents, types,
-  ccgutils, os, ropes, math, wordrecg, treetab, cgmeth,
+  ccgutils, ropes, wordrecg, treetab, cgmeth,
   rodutils, renderer, cgendata, aliases,
-  lowerings, tables, sets, ndi, lineinfos, pathutils, transf,
+  lowerings, ndi, lineinfos, pathutils, transf,
   injectdestructors, astmsgs, modulepaths, backendpragmas
 
 from expanddefaults import caseObjDefaultBranch
@@ -27,10 +27,10 @@ when defined(nimPreviewSlimSystem):
 when not defined(leanCompiler):
   import spawn, semparallel
 
-import strutils except `%`, addf # collides with ropes.`%`
+import std/strutils except `%`, addf # collides with ropes.`%`
 
 from ic / ic import ModuleBackendFlag
-import dynlib
+import std/[dynlib, math, tables, sets, os, intsets, hashes]
 
 when not declared(dynlib.libCandidates):
   proc libCandidates(s: string, dest: var seq[string]) =
@@ -121,7 +121,7 @@ proc getModuleDllPath(m: BModule, module: int): Rope =
 proc getModuleDllPath(m: BModule, s: PSym): Rope =
   result = getModuleDllPath(m.g.modules[s.itemId.module])
 
-import macros
+import std/macros
 
 proc cgFormatValue(result: var string; value: string) =
   result.add value

compiler/cgendata.nim

@@ -10,8 +10,10 @@
 ## This module contains the data structures for the C code generation phase.
 
 import
-  ast, ropes, options, intsets,
-  tables, ndi, lineinfos, pathutils, modulegraphs, sets
+  ast, ropes, options,
+  ndi, lineinfos, pathutils, modulegraphs
+
+import std/[intsets, tables, sets]
 
 type
   TLabel* = Rope              # for the C generator a label is just a rope

compiler/cgmeth.nim

@@ -10,9 +10,12 @@
 ## This module implements code generation for methods.
 
 import
-  intsets, options, ast, msgs, idents, renderer, types, magicsys,
+  options, ast, msgs, idents, renderer, types, magicsys,
   sempass2, modulegraphs, lineinfos
 
+
+import std/intsets
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/closureiters.nim

@@ -134,7 +134,9 @@
 import
   ast, msgs, idents,
   renderer, magicsys, lowerings, lambdalifting, modulegraphs, lineinfos,
-  tables, options
+  options
+
+import std/tables
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/cmdlinehelper.nim

@@ -11,7 +11,9 @@
 
 import
   options, idents, nimconf, extccomp, commands, msgs,
-  lineinfos, modulegraphs, condsyms, os, pathutils, parseopt
+  lineinfos, modulegraphs, condsyms, pathutils
+
+import std/[os, parseopt]
 
 proc prependCurDir*(f: AbsoluteFile): AbsoluteFile =
   when defined(unix):

compiler/commands.nim

@@ -27,7 +27,9 @@ bootSwitch(usedNoGC, defined(nogc), "--gc:none")
 import std/[setutils, os, strutils, parseutils, parseopt, sequtils, strtabs]
 import
   msgs, options, nversion, condsyms, extccomp, platform,
-  wordrecg, nimblecmd, lineinfos, pathutils, pathnorm
+  wordrecg, nimblecmd, lineinfos, pathutils
+
+import std/pathnorm
 
 from ast import setUseIc, eqTypeFlags, tfGcSafe, tfNoSideEffect
 

compiler/concepts.nim

@@ -11,7 +11,9 @@
 ## for details. Note this is a first implementation and only the "Concept matching"
 ## section has been implemented.
 
-import ast, astalgo, semdata, lookups, lineinfos, idents, msgs, renderer, types, intsets
+import ast, astalgo, semdata, lookups, lineinfos, idents, msgs, renderer, types
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/condsyms.nim

@@ -10,7 +10,7 @@
 # This module handles the conditional symbols.
 
 import
-  strtabs
+  std/strtabs
 
 from options import Feature
 from lineinfos import hintMin, hintMax, warnMin, warnMax
@@ -162,3 +162,4 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasNolineTooLong")
 
   defineSymbol("nimHasCastExtendedVm")
+  defineSymbol("nimHasWarnStdPrefix")

compiler/depends.nim

@@ -14,7 +14,7 @@ import options, ast, ropes, pathutils, msgs, lineinfos
 import modulegraphs
 
 import std/[os, parseutils]
-import strutils except addf
+import std/strutils except addf
 import std/private/globs
 
 when defined(nimPreviewSlimSystem):

compiler/dfa.nim

@@ -22,8 +22,9 @@
 ## "A Graph–Free Approach to Data–Flow Analysis" by Markus Mohnen.
 ## https://link.springer.com/content/pdf/10.1007/3-540-45937-5_6.pdf
 
-import ast, intsets, lineinfos, renderer, aliasanalysis
+import ast, lineinfos, renderer, aliasanalysis
 import std/private/asciitables
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/docgen.nim

@@ -15,15 +15,16 @@
 ## For corresponding users' documentation see [Nim DocGen Tools Guide].
 
 import
-  ast, strutils, strtabs, algorithm, sequtils, options, msgs, os, idents,
+  ast, options, msgs, idents,
   wordrecg, syntaxes, renderer, lexer,
   packages/docutils/[rst, rstidx, rstgen, dochelpers],
-  json, xmltree, trees, types,
-  typesrenderer, astalgo, lineinfos, intsets,
-  pathutils, tables, nimpaths, renderverbatim, osproc, packages
+  trees, types,
+  typesrenderer, astalgo, lineinfos,
+  pathutils, nimpaths, renderverbatim, packages
 import packages/docutils/rstast except FileIndex, TLineInfo
 
-from uri import encodeUrl
+import std/[os, strutils, strtabs, algorithm, json, osproc, tables, intsets, xmltree, sequtils]
+from std/uri import encodeUrl
 from nodejs import findNodeJs
 
 when defined(nimPreviewSlimSystem):

compiler/errorhandling.nim

@@ -10,7 +10,8 @@
 ## This module contains support code for new-styled error
 ## handling via an `nkError` node kind.
 
-import ast, renderer, options, strutils, types
+import ast, renderer, options, types
+import std/strutils
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/evalffi.nim

@@ -9,10 +9,12 @@
 
 ## This file implements the FFI part of the evaluator for Nim code.
 
-import ast, types, options, tables, dynlib, msgs, lineinfos
-from os import getAppFilename
+import ast, types, options, msgs, lineinfos
+from std/os import getAppFilename
 import libffi/libffi
 
+import std/[tables, dynlib]
+
 when defined(windows):
   const libcDll = "msvcrt.dll"
 elif defined(linux):

compiler/evaltempl.nim

@@ -9,8 +9,8 @@
 
 ## Template evaluation engine. Now hygienic.
 
-import
-  strutils, options, ast, astalgo, msgs, renderer, lineinfos, idents, trees
+import options, ast, astalgo, msgs, renderer, lineinfos, idents, trees
+import std/strutils
 
 type
   TemplCtx = object

compiler/filter_tmpl.nim

@@ -10,9 +10,11 @@
 # This module implements Nim's standard template filter.
 
 import
-  llstream, strutils, ast, msgs, options,
+  llstream, ast, msgs, options,
   filters, lineinfos, pathutils
 
+import std/strutils
+
 type
   TParseState = enum
     psDirective, psTempl

compiler/filters.nim

@@ -10,9 +10,11 @@
 # This module implements Nim's simple filters and helpers for filters.
 
 import
-  llstream, idents, strutils, ast, msgs, options,
+  llstream, idents, ast, msgs, options,
   renderer, pathutils
 
+import std/strutils
+
 proc invalidPragma(conf: ConfigRef; n: PNode) =
   localError(conf, n.info,
       "'$1' not allowed here" % renderTree(n, {renderNoComments}))

compiler/gorgeimpl.nim

@@ -9,8 +9,9 @@
 
 ## Module that implements ``gorge`` for the compiler.
 
-import msgs, os, osproc, streams, options,
-  lineinfos, pathutils
+import msgs, options, lineinfos, pathutils
+
+import std/[os, osproc, streams]
 
 when defined(nimPreviewSlimSystem):
   import std/syncio

compiler/guards.nim

@@ -870,7 +870,7 @@ template isSub(x): untyped = x.getMagic in someSub
 template isVal(x): untyped = x.kind in {nkCharLit..nkUInt64Lit}
 template isIntVal(x, y): untyped = x.intVal == y
 
-import macros
+import std/macros
 
 macro `=~`(x: PNode, pat: untyped): bool =
   proc m(x, pat, conds: NimNode) =

compiler/ic/bitabs.nim

@@ -1,7 +1,8 @@
 ## A BiTable is a table that can be seen as an optimized pair
 ## of `(Table[LitId, Val], Table[Val, LitId])`.
 
-import hashes, rodfiles
+import std/hashes
+import rodfiles
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/ic/cbackend.nim

@@ -18,7 +18,7 @@
 ## also doing cross-module dependency tracking and DCE that we don't need
 ## anymore. DCE is now done as prepass over the entire packed module graph.
 
-import std/packedsets, algorithm, tables
+import std/[packedsets, algorithm, tables]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/ic/ic.nim

@@ -7,12 +7,12 @@
 #    distribution, for details about the copyright.
 #
 
-import hashes, tables, intsets
+import std/[hashes, tables, intsets]
 import packed_ast, bitabs, rodfiles
 import ".." / [ast, idents, lineinfos, msgs, ropes, options,
   pathutils, condsyms, packages, modulepaths]
 #import ".." / [renderer, astalgo]
-from os import removeFile, isAbsolute
+from std/os import removeFile, isAbsolute
 
 import ../../dist/checksums/src/checksums/sha1
 

compiler/ic/integrity.nim

@@ -10,7 +10,7 @@
 ## Integrity checking for a set of .rod files.
 ## The set must cover a complete Nim project.
 
-import sets
+import std/sets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/ic/navigator.nim

@@ -11,9 +11,9 @@
 ## IDE-like features. It uses the set of .rod files to accomplish
 ## its task. The set must cover a complete Nim project.
 
-import sets
+import std/sets
 
-from os import nil
+from std/os import nil
 from std/private/miscdollars import toLocation
 
 when defined(nimPreviewSlimSystem):

compiler/ic/packed_ast.nim

@@ -12,7 +12,7 @@
 ## use this representation directly in all the transformations,
 ## it is superior.
 
-import hashes, tables, strtabs
+import std/[hashes, tables, strtabs]
 import bitabs
 import ".." / [ast, options]
 

compiler/ic/replayer.nim

@@ -14,7 +14,7 @@
 import ".." / [ast, modulegraphs, trees, extccomp, btrees,
   msgs, lineinfos, pathutils, options, cgmeth]
 
-import tables
+import std/tables
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/ic/rodfiles.nim

@@ -14,7 +14,7 @@
 ##     compiler works and less a storage format, you're probably looking for
 ##     the `ic` or `packed_ast` modules to understand the logical format.
 
-from typetraits import supportsCopyMem
+from std/typetraits import supportsCopyMem
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]

compiler/idents.nim

@@ -11,8 +11,8 @@
 # An identifier is a shared immutable string that can be compared by its
 # id. This module is essential for the compiler's performance.
 
-import
-  hashes, wordrecg
+import wordrecg
+import std/hashes
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/importer.nim

@@ -10,11 +10,12 @@
 ## This module implements the symbol importing mechanism.
 
 import
-  intsets, ast, astalgo, msgs, options, idents, lookups,
-  semdata, modulepaths, sigmatch, lineinfos, sets,
-  modulegraphs, wordrecg, tables
-from strutils import `%`
-from sequtils import addUnique
+  ast, astalgo, msgs, options, idents, lookups,
+  semdata, modulepaths, sigmatch, lineinfos,
+  modulegraphs, wordrecg
+from std/strutils import `%`, startsWith
+from std/sequtils import addUnique
+import std/[sets, tables, intsets]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -301,6 +302,10 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
       var prefix = ""
       if realModule.constraint != nil: prefix = realModule.constraint.strVal & "; "
       message(c.config, n.info, warnDeprecated, prefix & realModule.name.s & " is deprecated")
+    let moduleName = getModuleName(c.config, n)
+    if belongsToStdlib(c.graph, result) and not startsWith(moduleName, stdPrefix) and
+        not startsWith(moduleName, "system/") and not startsWith(moduleName, "packages/"):
+      message(c.config, n.info, warnStdPrefix, realModule.name.s)
     suggestSym(c.graph, n.info, result, c.graph.usageSym, false)
     importStmtResult.add newSymNode(result, n.info)
     #newStrNode(toFullPath(c.config, f), n.info)

compiler/injectdestructors.nim

@@ -14,11 +14,13 @@
 ## See doc/destructors.rst for a spec of the implemented rewrite rules
 
 import
-  intsets, strtabs, ast, astalgo, msgs, renderer, magicsys, types, idents,
-  strutils, options, lowerings, tables, modulegraphs,
+  ast, astalgo, msgs, renderer, magicsys, types, idents,
+  options, lowerings, modulegraphs,
   lineinfos, parampatterns, sighashes, liftdestructors, optimizer,
   varpartitions, aliasanalysis, dfa, wordrecg
 
+import std/[strtabs, tables, strutils, intsets]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/int128.nim

@@ -3,7 +3,7 @@
 ## hold all from `low(BiggestInt)` to `high(BiggestUInt)`, This
 ## type is for that purpose.
 
-from math import trunc
+from std/math import trunc
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -358,7 +358,7 @@ proc `*`*(lhs, rhs: Int128): Int128 =
 proc `*=`*(a: var Int128, b: Int128) =
   a = a * b
 
-import bitops
+import std/bitops
 
 proc fastLog2*(a: Int128): int =
   result = 0

compiler/isolation_check.nim

@@ -11,7 +11,9 @@
 ## https://github.com/nim-lang/RFCs/issues/244 for more details.
 
 import
-  ast, types, renderer, intsets
+  ast, types, renderer
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/jsgen.nim

@@ -37,8 +37,8 @@ import
 
 import pipelineutils
 
-import json, sets, math, tables, intsets
-import strutils except addf
+import std/[json, sets, math, tables, intsets]
+import std/strutils except addf
 
 when defined(nimPreviewSlimSystem):
   import std/[assertions, syncio]

compiler/lambdalifting.nim

@@ -10,10 +10,12 @@
 # This file implements lambda lifting for the transformator.
 
 import
-  intsets, strutils, options, ast, astalgo, msgs,
-  idents, renderer, types, magicsys, lowerings, tables, modulegraphs, lineinfos,
+  options, ast, astalgo, msgs,
+  idents, renderer, types, magicsys, lowerings, modulegraphs, lineinfos,
   transf, liftdestructors, typeallowed
 
+import std/[strutils, tables, intsets]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/lexer.nim

@@ -16,8 +16,10 @@
 # DOS or Macintosh text files, even when it is not the native format.
 
 import
-  hashes, options, msgs, strutils, platform, idents, nimlexbase, llstream,
-  wordrecg, lineinfos, pathutils, parseutils
+  options, msgs, platform, idents, nimlexbase, llstream,
+  wordrecg, lineinfos, pathutils
+
+import std/[hashes, parseutils, strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]

compiler/liftdestructors.nim

@@ -11,8 +11,9 @@
 ## (`=sink`, `=copy`, `=destroy`, `=deepCopy`, `=wasMoved`, `=dup`).
 
 import modulegraphs, lineinfos, idents, ast, renderer, semdata,
-  sighashes, lowerings, options, types, msgs, magicsys, tables, ccgutils
+  sighashes, lowerings, options, types, msgs, magicsys, ccgutils
 
+import std/tables
 from trees import isCaseObj
 
 when defined(nimPreviewSlimSystem):

compiler/liftlocals.nim

@@ -10,9 +10,11 @@
 ## This module implements the '.liftLocals' pragma.
 
 import
-  strutils, options, ast, msgs,
+  options, ast, msgs,
   idents, renderer, types, lowerings, lineinfos
 
+import std/strutils
+
 from pragmas import getPragmaVal
 from wordrecg import wLiftLocals
 

compiler/lineinfos.nim

@@ -10,7 +10,8 @@
 ## This module contains the `TMsgKind` enum as well as the
 ## `TLineInfo` object.
 
-import ropes, tables, pathutils, hashes
+import ropes, pathutils
+import std/[hashes, tables]
 
 const
   explanationsBaseUrl* = "https://nim-lang.github.io/Nim"
@@ -91,6 +92,7 @@ type
     warnStmtListLambda = "StmtListLambda",
     warnBareExcept = "BareExcept",
     warnImplicitDefaultValue = "ImplicitDefaultValue",
+    warnStdPrefix = "StdPrefix"
     warnUser = "User",
     # hints
     hintSuccess = "Success", hintSuccessX = "SuccessX",
@@ -194,6 +196,7 @@ const
     warnStmtListLambda: "statement list expression assumed to be anonymous proc; this is deprecated, use `do (): ...` or `proc () = ...` instead",
     warnBareExcept: "$1",
     warnImplicitDefaultValue: "$1",
+    warnStdPrefix: "$1 needs the 'std' prefix",
     warnUser: "$1",
     hintSuccess: "operation successful: $#",
     # keep in sync with `testament.isSuccess`
@@ -249,7 +252,7 @@ type
 
 proc computeNotesVerbosity(): array[0..3, TNoteKinds] =
   result = default(array[0..3, TNoteKinds])
-  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept}
+  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept, warnStdPrefix}
   result[2] = result[3] - {hintStackTrace, hintExtendedContext, hintDeclaredLoc, hintProcessingStmt}
   result[1] = result[2] - {warnProveField, warnProveIndex,
     warnGcUnsafe, hintPath, hintDependency, hintCodeBegin, hintCodeEnd,

compiler/lookups.nim

@@ -14,8 +14,10 @@ when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import
-  intsets, ast, astalgo, idents, semdata, types, msgs, options,
-  renderer, lineinfos, modulegraphs, astmsgs, sets, wordrecg
+  ast, astalgo, idents, semdata, types, msgs, options,
+  renderer, lineinfos, modulegraphs, astmsgs, wordrecg
+
+import std/[intsets, sets]
 
 proc ensureNoMissingOrUnusedSymbols(c: PContext; scope: PScope)
 
@@ -464,7 +466,7 @@ proc mergeShadowScope*(c: PContext) =
       c.addInterfaceDecl(sym)
 
 
-import std/editdistance, heapqueue
+import std/[editdistance, heapqueue]
 
 type SpellCandidate = object
   dist: int

compiler/modulegraphs.nim

@@ -11,7 +11,7 @@
 ## represents a complete Nim project. Single modules can either be kept in RAM
 ## or stored in a rod-file.
 
-import intsets, tables, hashes
+import std/[intsets, tables, hashes]
 import ../dist/checksums/src/checksums/md5
 import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages
 import ic / [packed_ast, ic]

compiler/modulepaths.nim

@@ -7,9 +7,11 @@
 #    distribution, for details about the copyright.
 #
 
-import ast, renderer, strutils, msgs, options, idents, os, lineinfos,
+import ast, renderer, msgs, options, idents, lineinfos,
   pathutils
 
+import std/[strutils, os]
+
 proc getModuleName*(conf: ConfigRef; n: PNode): string =
   # This returns a short relative module name without the nim extension
   # e.g. like "system", "importer" or "somepath/module"

compiler/nilcheck.nim

@@ -7,8 +7,8 @@
 #    distribution, for details about the copyright.
 #
 
-import ast, renderer, intsets, tables, msgs, options, lineinfos, strformat, idents, treetab, hashes
-import sequtils, strutils, sets
+import ast, renderer, msgs, options, lineinfos, idents, treetab
+import std/[intsets, tables, sequtils, strutils, sets, strformat, hashes]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/nim.cfg

@@ -41,6 +41,7 @@ define:useStdoutAsStdmsg
 @end
 
 @if nimHasWarnBareExcept:
+  warning[BareExcept]:on
   warningAserror[BareExcept]:on
 @end
 
@@ -51,3 +52,7 @@ define:useStdoutAsStdmsg
   warningAsError[ProveInit]:on
 @end
 
+@if nimHasWarnStdPrefix:
+  warning[StdPrefix]:on
+  warningAsError[StdPrefix]:on
+@end

compiler/nim.nim

@@ -28,7 +28,7 @@ import
   commands, options, msgs, extccomp, main, idents, lineinfos, cmdlinehelper,
   pathutils, modulegraphs
 
-from browsers import openDefaultBrowser
+from std/browsers import openDefaultBrowser
 from nodejs import findNodeJs
 
 when hasTinyCBackend:

compiler/nimblecmd.nim

@@ -9,8 +9,9 @@
 
 ## Implements some helper procs for Nimble (Nim's package manager) support.
 
-import parseutils, strutils, os, options, msgs, sequtils, lineinfos, pathutils,
-  tables
+import options, msgs, lineinfos, pathutils
+
+import std/[parseutils, strutils, os, tables, sequtils]
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]

compiler/nimconf.nim

@@ -10,8 +10,10 @@
 # This module handles the reading of the config file.
 
 import
-  llstream, commands, os, strutils, msgs, lexer, ast,
-  options, idents, wordrecg, strtabs, lineinfos, pathutils, scriptconfig
+  llstream, commands, msgs, lexer, ast,
+  options, idents, wordrecg, lineinfos, pathutils, scriptconfig
+
+import std/[os, strutils, strtabs]
 
 when defined(nimPreviewSlimSystem):
   import std/syncio

compiler/nimlexbase.nim

@@ -12,8 +12,9 @@
 # handling that exists! Only at line endings checks are necessary
 # if the buffer needs refilling.
 
-import
-  llstream, strutils
+import llstream
+
+import std/strutils
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/nimpaths.nim

@@ -17,7 +17,7 @@ interpolation variables:
 Unstable API
 ]##
 
-import os, strutils
+import std/[os, strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/nir/nir.nim

@@ -10,7 +10,7 @@
 ## Nim Intermediate Representation, designed to capture all of Nim's semantics without losing too much
 ## precious information. Can easily be translated into C. And to JavaScript, hopefully.
 
-from os import addFileExt, `/`, createDir
+from std/os import addFileExt, `/`, createDir
 
 import std / assertions
 import ".." / [ast, modulegraphs, renderer, transf, options, msgs, lineinfos]

compiler/nir/stringcases.nim

@@ -49,7 +49,7 @@ afterCase: ...
 # Every string of length > position for which s[position] <= char is in one
 # set else it is in the other set.
 
-from sequtils import addUnique
+from std/sequtils import addUnique
 
 type
   Key = (LitId, LabelId)

compiler/nodejs.nim

@@ -1,4 +1,4 @@
-import os
+import std/os
 
 proc findNodeJs*(): string {.inline.} =
   ## Find NodeJS executable and return it as a string.

compiler/optimizer.nim

@@ -12,11 +12,11 @@
 ## - recognize "all paths lead to 'wasMoved(x)'"
 
 import
-  ast, renderer, idents, intsets
+  ast, renderer, idents
 
 from trees import exprStructuralEquivalent
 
-import std/strutils
+import std/[strutils, intsets]
 
 const
   nfMarkForDeletion = nfNone # faster than a lookup table

compiler/options.nim

@@ -8,11 +8,12 @@
 #
 
 import
-  os, strutils, strtabs, sets, lineinfos, platform,
-  prefixmatches, pathutils, nimpaths, tables
+  lineinfos, platform,
+  prefixmatches, pathutils, nimpaths
 
-from terminal import isatty
-from times import utc, fromUnix, local, getTime, format, DateTime
+import std/[tables, os, strutils, strtabs, sets]
+from std/terminal import isatty
+from std/times import utc, fromUnix, local, getTime, format, DateTime
 from std/private/globs import nativeToUnixPath
 
 when defined(nimPreviewSlimSystem):
@@ -890,7 +891,7 @@ const stdlibDirs* = [
 
 const
   pkgPrefix = "pkg/"
-  stdPrefix = "std/"
+  stdPrefix* = "std/"
 
 proc getRelativePathFromConfigPath*(conf: ConfigRef; f: AbsoluteFile, isTitle = false): RelativeFile =
   result = RelativeFile("")

compiler/parampatterns.nim

@@ -10,9 +10,11 @@
 ## This module implements the pattern matching features for term rewriting
 ## macro support.
 
-import strutils, ast, types, msgs, idents, renderer, wordrecg, trees,
+import ast, types, msgs, idents, renderer, wordrecg, trees,
   options
 
+import std/strutils
+
 # we precompile the pattern here for efficiency into some internal
 # stack based VM :-) Why? Because it's fun; I did no benchmarks to see if that
 # actually improves performance.

compiler/parser.nim

@@ -49,9 +49,11 @@ when isMainModule or defined(nimTestGrammar):
     checkGrammarFile()
 
 import
-  llstream, lexer, idents, strutils, ast, msgs, options, lineinfos,
+  llstream, lexer, idents, ast, msgs, options, lineinfos,
   pathutils
 
+import std/strutils
+
 when defined(nimpretty):
   import layouter
 

compiler/pathutils.nim

@@ -10,7 +10,7 @@
 ## Path handling utilities for Nim. Strictly typed code in order
 ## to avoid the never ending time sink in getting path handling right.
 
-import os, pathnorm, strutils
+import std/[os, pathnorm, strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]

compiler/platform.nim

@@ -14,7 +14,7 @@
 # Feel free to test for your excentric platform!
 
 import
-  strutils
+  std/strutils
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/pragmas.nim

@@ -10,10 +10,12 @@
 # This module implements semantic checking for pragmas
 
 import
-  os, condsyms, ast, astalgo, idents, semdata, msgs, renderer,
-  wordrecg, ropes, options, strutils, extccomp, math, magicsys, trees,
+  condsyms, ast, astalgo, idents, semdata, msgs, renderer,
+  wordrecg, ropes, options, extccomp, magicsys, trees,
   types, lookups, lineinfos, pathutils, linter, modulepaths
 
+import std/[os, math, strutils]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/prefixmatches.nim

@@ -7,7 +7,7 @@
 #    distribution, for details about the copyright.
 #
 
-from strutils import toLowerAscii
+from std/strutils import toLowerAscii
 
 type
   PrefixMatch* {.pure.} = enum

compiler/procfind.nim

@@ -11,7 +11,9 @@
 # This is needed for proper handling of forward declarations.
 
 import
-  ast, astalgo, msgs, semdata, types, trees, strutils, lookups
+  ast, astalgo, msgs, semdata, types, trees, lookups
+
+import std/strutils
 
 proc equalGenericParams(procA, procB: PNode): bool =
   if procA.len != procB.len: return false

compiler/renderer.nim

@@ -14,7 +14,9 @@
 {.used.}
 
 import
-  lexer, options, idents, strutils, ast, msgs, lineinfos, wordrecg
+  lexer, options, idents, ast, msgs, lineinfos, wordrecg
+
+import std/[strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions, formatfloat]

compiler/renderverbatim.nim

@@ -1,4 +1,4 @@
-import strutils
+import std/strutils
 
 import ast, options, msgs
 

compiler/reorder.nim

@@ -1,9 +1,11 @@
 
 import
-  intsets, ast, idents, algorithm, renderer, strutils,
+  ast, idents, renderer,
   msgs, modulegraphs, syntaxes, options, modulepaths,
   lineinfos
 
+import std/[algorithm, strutils, intsets]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/rodutils.nim

@@ -8,7 +8,7 @@
 #
 
 ## Serialization utilities for the compiler.
-import strutils, math
+import std/[strutils, math]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/scriptconfig.nim

@@ -13,14 +13,16 @@
 import
   ast, modules, idents, condsyms,
   options, llstream, vm, vmdef, commands,
-  os, times, osproc, wordrecg, strtabs, modulegraphs,
+  wordrecg, modulegraphs,
   pathutils, pipelines
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
 
+import std/[strtabs, os, times, osproc]
+
 # we support 'cmpIgnoreStyle' natively for efficiency:
-from strutils import cmpIgnoreStyle, contains
+from std/strutils import cmpIgnoreStyle, contains
 
 proc listDirs(a: VmArgs, filter: set[PathComponent]) =
   let dir = getString(a, 0)

compiler/sem.nim

@@ -9,19 +9,18 @@
 
 # This module implements the semantic checking pass.
 
-import tables
-
 import
-  ast, strutils, options, astalgo, trees,
-  wordrecg, ropes, msgs, idents, renderer, types, platform, math,
+  ast, options, astalgo, trees,
+  wordrecg, ropes, msgs, idents, renderer, types, platform,
   magicsys, nversion, nimsets, semfold, modulepaths, importer,
   procfind, lookups, pragmas, semdata, semtypinst, sigmatch,
-  intsets, transf, vmdef, vm, aliases, cgmeth, lambdalifting,
+  transf, vmdef, vm, aliases, cgmeth, lambdalifting,
   evaltempl, patterns, parampatterns, sempass2, linter, semmacrosanity,
-  lowerings, plugins/active, lineinfos, strtabs, int128,
+  lowerings, plugins/active, lineinfos, int128,
   isolation_check, typeallowed, modulegraphs, enumtostr, concepts, astmsgs,
   extccomp
 
+import std/[strtabs, math, tables, intsets, strutils]
 
 when not defined(leanCompiler):
   import spawn

compiler/semdata.nim

@@ -9,14 +9,14 @@
 
 ## This module contains the data structures for the semantic checking phase.
 
-import tables
+import std/[tables, intsets, sets]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import
-  intsets, options, ast, astalgo, msgs, idents, renderer,
-  magicsys, vmdef, modulegraphs, lineinfos, sets, pathutils
+  options, ast, astalgo, msgs, idents, renderer,
+  magicsys, vmdef, modulegraphs, lineinfos, pathutils
 
 import ic / ic
 

compiler/semfold.nim

@@ -11,10 +11,11 @@
 # and evaluation phase
 
 import
-  strutils, options, ast, trees, nimsets,
-  platform, math, msgs, idents, renderer, types,
-  commands, magicsys, modulegraphs, strtabs, lineinfos, wordrecg
+  options, ast, trees, nimsets,
+  platform, msgs, idents, renderer, types,
+  commands, magicsys, modulegraphs, lineinfos, wordrecg
 
+import std/[strutils, math, strtabs]
 from system/memory import nimCStrLen
 
 when defined(nimPreviewSlimSystem):

compiler/semobjconstr.nim

@@ -11,7 +11,7 @@
 
 # included from sem.nim
 
-from sugar import dup
+from std/sugar import dup
 
 type
   ObjConstrContext = object

compiler/semparallel.nim

@@ -26,7 +26,7 @@ import
   renderer, types, modulegraphs, options, spawn, lineinfos
 
 from trees import getMagic, getRoot
-from strutils import `%`
+from std/strutils import `%`
 
 discard """
 

compiler/sempass2.nim

@@ -8,11 +8,13 @@
 #
 
 import
-  intsets, ast, astalgo, msgs, renderer, magicsys, types, idents, trees,
-  wordrecg, strutils, options, guards, lineinfos, semfold, semdata,
-  modulegraphs, varpartitions, typeallowed, nilcheck, errorhandling, tables,
+  ast, astalgo, msgs, renderer, magicsys, types, idents, trees,
+  wordrecg, options, guards, lineinfos, semfold, semdata,
+  modulegraphs, varpartitions, typeallowed, nilcheck, errorhandling,
   semstrictfuncs
 
+import std/[tables, intsets, strutils]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/sighashes.nim

@@ -9,8 +9,9 @@
 
 ## Computes hash values for routine (proc, method etc) signatures.
 
-import ast, tables, ropes, modulegraphs, options, msgs, pathutils
-from hashes import Hash
+import ast, ropes, modulegraphs, options, msgs, pathutils
+from std/hashes import Hash
+import std/tables
 import types
 import ../dist/checksums/src/checksums/md5
 

compiler/sigmatch.nim

@@ -11,10 +11,12 @@
 ## the call to overloaded procs, generic procs and operators.
 
 import
-  intsets, ast, astalgo, semdata, types, msgs, renderer, lookups, semtypinst,
-  magicsys, idents, lexer, options, parampatterns, strutils, trees,
+  ast, astalgo, semdata, types, msgs, renderer, lookups, semtypinst,
+  magicsys, idents, lexer, options, parampatterns, trees,
   linter, lineinfos, lowerings, modulegraphs, concepts
 
+import std/[intsets, strutils]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 

compiler/suggest.nim

@@ -32,11 +32,13 @@
 
 # included from sigmatch.nim
 
-import algorithm, sets, prefixmatches, parseutils, tables
+import prefixmatches
 from wordrecg import wDeprecated, wError, wAddr, wYield
 
+import std/[algorithm, sets, parseutils, tables]
+
 when defined(nimsuggest):
-  import tables, pathutils # importer
+  import std/tables, pathutils # importer
 
 const
   sep = '\t'

compiler/syntaxes.nim

@@ -10,9 +10,10 @@
 ## Implements the dispatcher for the different parsers.
 
 import
-  strutils, llstream, ast, idents, lexer, options, msgs, parser,
+  llstream, ast, idents, lexer, options, msgs, parser,
   filters, filter_tmpl, renderer, lineinfos, pathutils
 
+import std/strutils
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
 

compiler/treetab.nim

@@ -9,8 +9,9 @@
 
 # Implements a table from trees to trees. Does structural equivalence checking.
 
-import
-  hashes, ast, astalgo, types
+import ast, astalgo, types
+
+import std/hashes
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/typeallowed.nim

@@ -10,8 +10,8 @@
 ## This module contains 'typeAllowed' and friends which check
 ## for invalid types like `openArray[var int]`.
 
-import
-  intsets, ast, renderer, options, semdata, types
+import ast, renderer, options, semdata, types
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/types.nim

@@ -10,9 +10,11 @@
 # this module contains routines for accessing and iterating over types
 
 import
-  intsets, ast, astalgo, trees, msgs, strutils, platform, renderer, options,
+  ast, astalgo, trees, msgs, platform, renderer, options,
   lineinfos, int128, modulegraphs, astmsgs
 
+import std/[intsets, strutils]
+
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]
 

compiler/typesrenderer.nim

@@ -7,7 +7,8 @@
 #    distribution, for details about the copyright.
 #
 
-import renderer, strutils, ast, types
+import renderer, ast, types
+import std/strutils
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/vmdeps.nim

@@ -7,9 +7,11 @@
 #    distribution, for details about the copyright.
 #
 
-import ast, types, msgs, os, options, idents, lineinfos
+import ast, types, msgs, options, idents, lineinfos
 from pathutils import AbsoluteFile
 
+import std/os
+
 when defined(nimPreviewSlimSystem):
   import std/syncio
 

compiler/vmgen.nim

@@ -26,14 +26,14 @@
 # solves the opcLdConst vs opcAsgnConst issue. Of course whether we need
 # this copy depends on the involved types.
 
-import tables
+import std/[tables, intsets, strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import
-  strutils, ast, types, msgs, renderer, vmdef, trees,
-  intsets, magicsys, options, lowerings, lineinfos, transf, astmsgs
+  ast, types, msgs, renderer, vmdef, trees,
+  magicsys, options, lowerings, lineinfos, transf, astmsgs
 
 from modulegraphs import getBody
 

compiler/vmmarshal.nim

@@ -9,9 +9,11 @@
 
 ## Implements marshaling for the VM.
 
-import streams, json, intsets, tables, ast, astalgo, idents, types, msgs,
+import ast, astalgo, idents, types, msgs,
   options, lineinfos
 
+import std/[streams, json, intsets, tables]
+
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]
 

compiler/vmprofiler.nim

@@ -1,7 +1,7 @@
 
-import
-  options, vmdef, times, lineinfos, strutils, tables,
-  msgs
+import options, vmdef, lineinfos, msgs
+
+import std/[times, strutils, tables]
 
 proc enter*(prof: var Profiler, c: PCtx, tos: PStackFrame) {.inline.} =
   if optProfileVM in c.config.globalOptions:

compiler/wordrecg.nim

@@ -145,6 +145,6 @@ const
 
 
 from std/enumutils import genEnumCaseStmt
-from strutils import normalize
+from std/strutils import normalize
 proc findStr*[T: enum](a, b: static[T], s: string, default: T): T =
   genEnumCaseStmt(T, s, default, ord(a), ord(b), normalize)