2 % (c) The AQUA Project, Glasgow University, 1996-98
4 \section[CmdLineOpts]{Things to do with command-line options}
29 opt_D_dump_occur_anal,
35 opt_D_dump_simpl_iterations,
36 opt_D_dump_simpl_stats,
42 opt_D_dump_worker_wrapper,
47 opt_D_dump_minimal_imports,
49 opt_D_verbose_core2core,
50 opt_D_verbose_stg2stg,
59 opt_WarnDuplicateExports,
61 opt_WarnIncompletePatterns,
62 opt_WarnMissingFields,
63 opt_WarnMissingMethods,
65 opt_WarnNameShadowing,
66 opt_WarnOverlappingPatterns,
67 opt_WarnSimplePatterns,
70 opt_WarnUnusedImports,
71 opt_WarnUnusedMatches,
75 opt_AutoSccsOnAllToplevs,
76 opt_AutoSccsOnExportedToplevs,
77 opt_AutoSccsOnIndividualCafs,
85 opt_MaxContextReductionDepth,
86 opt_AllowOverlappingInstances,
87 opt_AllowUndecidableInstances,
89 opt_IrrefutableTuples,
98 opt_LiberateCaseThreshold,
99 opt_StgDoLetNoEscapes,
102 opt_UnboxStrictFields,
103 opt_SimplNoPreInlining,
104 opt_SimplDoEtaReduction,
105 opt_SimplDoLambdaEtaExpansion,
108 opt_SimplPedanticBottoms,
111 opt_UF_HiFileThreshold,
112 opt_UF_CreationThreshold,
114 opt_UF_ScrutConDiscount,
115 opt_UF_FunAppDiscount,
116 opt_UF_PrimArgDiscount,
117 opt_UF_KeenessFactor,
123 opt_EmitCExternDecls,
124 opt_EnsureSplittableC,
131 opt_IgnoreIfacePragmas,
133 opt_NoImplicitPrelude,
135 opt_OmitInterfacePragmas,
136 opt_ProduceExportCStubs,
137 opt_ProduceExportHStubs,
156 #include "HsVersions.h"
158 import Array ( array, (//) )
161 import Constants -- Default values for some flags
163 import FastString ( headFS )
164 import Maybes ( assocMaybe, firstJust, maybeToBool )
165 import Panic ( panic, panic# )
167 #if __GLASGOW_HASKELL__ < 301
168 import ArrBase ( Array(..) )
170 import PrelArr ( Array(..) )
174 A command-line {\em switch} is (generally) either on or off; e.g., the
175 ``verbose'' (-v) switch is either on or off.
177 A list of {\em ToDo}s is things to be done in a particular part of
178 processing. A (fictitious) example for the Core-to-Core simplifier
179 might be: run the simplifier, then run the strictness analyser, then
180 run the simplifier again (three ``todos'').
182 There are three ``to-do processing centers'' at the moment. In the
183 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
184 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
185 (\tr{simplStg/SimplStg.lhs}).
188 %************************************************************************
190 \subsection{Datatypes associated with command-line options}
192 %************************************************************************
196 = SwBool Bool -- on/off
197 | SwString FAST_STRING -- nothing or a String
198 | SwInt Int -- nothing or an Int
202 data CoreToDo -- These are diff core-to-core passes,
203 -- which may be invoked in any order,
204 -- as many times as you like.
206 = CoreDoSimplify -- The core-to-core simplifier.
207 (SimplifierSwitch -> SwitchResult)
208 -- Each run of the simplifier can take a different
209 -- set of simplifier-specific flags.
211 | CoreDoFloatOutwards Bool -- True <=> float lambdas to top level
216 | CoreDoWorkerWrapper
227 | StgDoMassageForProfiling -- should be (next to) last
228 -- There's also setStgVarInfo, but its absolute "lastness"
229 -- is so critical that it is hardwired in (no flag).
234 data SimplifierSwitch
235 = MaxSimplifierIterations Int
236 | SimplInlinePhase Int
242 %************************************************************************
244 \subsection{Classifying command-line options}
246 %************************************************************************
249 lookUp :: FAST_STRING -> Bool
250 lookup_int :: String -> Maybe Int
251 lookup_def_int :: String -> Int -> Int
252 lookup_def_float :: String -> Float -> Float
253 lookup_str :: String -> Maybe String
255 lookUp sw = maybeToBool (assoc_opts sw)
257 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
259 lookup_int sw = case (lookup_str sw) of
261 Just xx -> Just (read xx)
263 lookup_def_int sw def = case (lookup_str sw) of
264 Nothing -> def -- Use default
267 lookup_def_char sw def = case (lookup_str sw) of
269 _ -> def -- Use default
271 lookup_def_float sw def = case (lookup_str sw) of
272 Nothing -> def -- Use default
275 assoc_opts = assocMaybe [ (a, True) | a <- argv ]
276 unpacked_opts = map _UNPK_ argv
279 Putting the compiler options into temporary at-files
280 may turn out to be necessary later on if we turn hsc into
281 a pure Win32 application where I think there's a command-line
282 length limit of 255. unpacked_opts understands the @ option.
284 assoc_opts = assocMaybe [ (_PK_ a, True) | a <- unpacked_opts ]
286 unpacked_opts :: [String]
292 expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
298 src_filename :: FAST_STRING
299 src_filename = case argv of
300 filename : rest | headFS filename /= '-' -> filename
301 otherwise -> panic "no filename"
306 opt_D_dump_all {- do not -} = lookUp SLIT("-ddump-all")
307 opt_D_dump_most {- export -} = opt_D_dump_all || lookUp SLIT("-ddump-most")
309 opt_D_dump_absC = opt_D_dump_all || lookUp SLIT("-ddump-absC")
310 opt_D_dump_asm = opt_D_dump_all || lookUp SLIT("-ddump-asm")
311 opt_D_dump_cpranal = opt_D_dump_most || lookUp SLIT("-ddump-cpranal")
312 opt_D_dump_deriv = opt_D_dump_most || lookUp SLIT("-ddump-deriv")
313 opt_D_dump_ds = opt_D_dump_most || lookUp SLIT("-ddump-ds")
314 opt_D_dump_flatC = opt_D_dump_all || lookUp SLIT("-ddump-flatC")
315 opt_D_dump_foreign = opt_D_dump_most || lookUp SLIT("-ddump-foreign-stubs")
316 opt_D_dump_inlinings = opt_D_dump_all || lookUp SLIT("-ddump-inlinings")
317 opt_D_dump_occur_anal = opt_D_dump_all || lookUp SLIT("-ddump-occur-anal")
318 opt_D_dump_parsed = opt_D_dump_most || lookUp SLIT("-ddump-parsed")
319 opt_D_dump_realC = opt_D_dump_all || lookUp SLIT("-ddump-realC")
320 opt_D_dump_rn = opt_D_dump_most || lookUp SLIT("-ddump-rn")
321 opt_D_dump_simpl = opt_D_dump_most || lookUp SLIT("-ddump-simpl")
322 opt_D_dump_simpl_iterations = opt_D_dump_all || lookUp SLIT("-ddump-simpl-iterations")
323 opt_D_dump_spec = opt_D_dump_most || lookUp SLIT("-ddump-spec")
324 opt_D_dump_stg = opt_D_dump_most || lookUp SLIT("-ddump-stg")
325 opt_D_dump_stranal = opt_D_dump_most || lookUp SLIT("-ddump-stranal")
326 opt_D_dump_tc = opt_D_dump_most || lookUp SLIT("-ddump-tc")
327 opt_D_dump_rules = opt_D_dump_most || lookUp SLIT("-ddump-rules")
328 opt_D_dump_usagesp = opt_D_dump_most || lookUp SLIT("-ddump-usagesp")
329 opt_D_dump_cse = opt_D_dump_most || lookUp SLIT("-ddump-cse")
330 opt_D_dump_worker_wrapper = opt_D_dump_most || lookUp SLIT("-ddump-workwrap")
331 opt_D_show_passes = opt_D_dump_most || lookUp SLIT("-dshow-passes")
332 opt_D_dump_rn_trace = opt_D_dump_all || lookUp SLIT("-ddump-rn-trace")
333 opt_D_dump_rn_stats = opt_D_dump_most || lookUp SLIT("-ddump-rn-stats")
334 opt_D_dump_stix = opt_D_dump_all || lookUp SLIT("-ddump-stix")
335 opt_D_dump_simpl_stats = opt_D_dump_most || lookUp SLIT("-ddump-simpl-stats")
336 opt_D_source_stats = opt_D_dump_most || lookUp SLIT("-dsource-stats")
337 opt_D_verbose_core2core = opt_D_dump_all || lookUp SLIT("-dverbose-simpl")
338 opt_D_verbose_stg2stg = opt_D_dump_all || lookUp SLIT("-dverbose-stg")
339 opt_D_dump_minimal_imports = lookUp SLIT("-ddump-minimal-imports")
341 opt_DoCoreLinting = lookUp SLIT("-dcore-lint")
342 opt_DoStgLinting = lookUp SLIT("-dstg-lint")
343 opt_DoUSPLinting = lookUp SLIT("-dusagesp-lint")
344 opt_PprStyle_NoPrags = lookUp SLIT("-dppr-noprags")
345 opt_PprStyle_Debug = lookUp SLIT("-dppr-debug")
346 opt_PprUserLength = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
349 opt_WarnDuplicateExports = lookUp SLIT("-fwarn-duplicate-exports")
350 opt_WarnHiShadows = lookUp SLIT("-fwarn-hi-shadowing")
351 opt_WarnIncompletePatterns = lookUp SLIT("-fwarn-incomplete-patterns")
352 opt_WarnMissingFields = lookUp SLIT("-fwarn-missing-fields")
353 opt_WarnMissingMethods = lookUp SLIT("-fwarn-missing-methods")
354 opt_WarnMissingSigs = lookUp SLIT("-fwarn-missing-signatures")
355 opt_WarnNameShadowing = lookUp SLIT("-fwarn-name-shadowing")
356 opt_WarnOverlappingPatterns = lookUp SLIT("-fwarn-overlapping-patterns")
357 opt_WarnSimplePatterns = lookUp SLIT("-fwarn-simple-patterns")
358 opt_WarnTypeDefaults = lookUp SLIT("-fwarn-type-defaults")
359 opt_WarnUnusedBinds = lookUp SLIT("-fwarn-unused-binds")
360 opt_WarnUnusedImports = lookUp SLIT("-fwarn-unused-imports")
361 opt_WarnUnusedMatches = lookUp SLIT("-fwarn-unused-matches")
362 opt_WarnDeprecations = lookUp SLIT("-fwarn-deprecations")
365 opt_AutoSccsOnAllToplevs = lookUp SLIT("-fauto-sccs-on-all-toplevs")
366 opt_AutoSccsOnExportedToplevs = lookUp SLIT("-fauto-sccs-on-exported-toplevs")
367 opt_AutoSccsOnIndividualCafs = lookUp SLIT("-fauto-sccs-on-individual-cafs")
368 opt_AutoSccsOnDicts = lookUp SLIT("-fauto-sccs-on-dicts")
369 opt_SccProfilingOn = lookUp SLIT("-fscc-profiling")
370 opt_DoTickyProfiling = lookUp SLIT("-fticky-ticky")
373 opt_AllStrict = lookUp SLIT("-fall-strict")
374 opt_DictsStrict = lookUp SLIT("-fdicts-strict")
375 opt_AllowOverlappingInstances = lookUp SLIT("-fallow-overlapping-instances")
376 opt_AllowUndecidableInstances = lookUp SLIT("-fallow-undecidable-instances")
377 opt_GlasgowExts = lookUp SLIT("-fglasgow-exts")
378 opt_IrrefutableTuples = lookUp SLIT("-firrefutable-tuples")
379 opt_MaxContextReductionDepth = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
380 opt_NumbersStrict = lookUp SLIT("-fnumbers-strict")
381 opt_Parallel = lookUp SLIT("-fparallel")
382 opt_SMP = lookUp SLIT("-fsmp")
385 opt_DoEtaReduction = lookUp SLIT("-fdo-eta-reduction")
386 opt_DoSemiTagging = lookUp SLIT("-fsemi-tagging")
387 opt_FoldrBuildOn = lookUp SLIT("-ffoldr-build-on")
388 opt_LiberateCaseThreshold = lookup_def_int "-fliberate-case-threshold" (10::Int)
389 opt_StgDoLetNoEscapes = lookUp SLIT("-flet-no-escape")
390 opt_UnfoldCasms = lookUp SLIT("-funfold-casms-in-hi-file")
391 opt_UsageSPOn = lookUp SLIT("-fusagesp-on")
392 opt_UnboxStrictFields = lookUp SLIT("-funbox-strict-fields")
395 The optional '-inpackage=P' flag tells what package
396 we are compiling this module for.
397 The Prelude, for example is compiled with '-package prelude'
399 opt_InPackage = case lookup_str "-inpackage=" of
401 Nothing -> SLIT("Main") -- The package name if none is specified
403 opt_EmitCExternDecls = lookUp SLIT("-femit-extern-decls")
404 opt_EnsureSplittableC = lookUp SLIT("-fglobalise-toplev-names")
405 opt_GranMacros = lookUp SLIT("-fgransim")
406 opt_HiMap = lookup_str "-himap=" -- file saying where to look for .hi files
407 opt_HiMapSep = lookup_def_char "-himap-sep=" ':'
408 opt_HiVersion = lookup_def_int "-fhi-version=" 0 -- what version we're compiling.
409 opt_HistorySize = lookup_def_int "-fhistory-size" 20
410 opt_IgnoreAsserts = lookUp SLIT("-fignore-asserts")
411 opt_IgnoreIfacePragmas = lookUp SLIT("-fignore-interface-pragmas")
412 opt_NoHiCheck = lookUp SLIT("-fno-hi-version-check")
413 opt_NoImplicitPrelude = lookUp SLIT("-fno-implicit-prelude")
414 opt_OmitBlackHoling = lookUp SLIT("-dno-black-holing")
415 opt_OmitInterfacePragmas = lookUp SLIT("-fomit-interface-pragmas")
416 opt_ProduceExportCStubs = lookup_str "-F="
417 opt_ProduceExportHStubs = lookup_str "-FH="
418 opt_ProduceHi = lookup_str "-hifile=" -- the one to produce this time
420 -- Language for output: "C", "asm", "java", maybe more
421 -- Nothing => don't output anything
422 opt_OutputLanguage :: Maybe String
423 opt_OutputLanguage = lookup_str "-olang="
425 opt_OutputFile :: String
426 opt_OutputFile = case lookup_str "-ofile=" of
427 Nothing -> panic "No output file specified (-ofile=xxx)"
430 -- Simplifier switches
431 opt_SimplNoPreInlining = lookUp SLIT("-fno-pre-inlining")
432 -- NoPreInlining is there just to see how bad things
433 -- get if you don't do it!
434 opt_SimplDoEtaReduction = lookUp SLIT("-fdo-eta-reduction")
435 opt_SimplDoLambdaEtaExpansion = lookUp SLIT("-fdo-lambda-eta-expansion")
436 opt_SimplCaseOfCase = lookUp SLIT("-fcase-of-case")
437 opt_SimplCaseMerge = lookUp SLIT("-fcase-merge")
438 opt_SimplPedanticBottoms = lookUp SLIT("-fpedantic-bottoms")
441 opt_UF_HiFileThreshold = lookup_def_int "-funfolding-interface-threshold" (45::Int)
442 opt_UF_CreationThreshold = lookup_def_int "-funfolding-creation-threshold" (45::Int)
443 opt_UF_UseThreshold = lookup_def_int "-funfolding-use-threshold" (8::Int) -- Discounts can be big
444 opt_UF_ScrutConDiscount = lookup_def_int "-funfolding-con-discount" (2::Int)
445 opt_UF_FunAppDiscount = lookup_def_int "-funfolding-fun-discount" (6::Int) -- It's great to inline a fn
446 opt_UF_PrimArgDiscount = lookup_def_int "-funfolding-prim-discount" (1::Int)
447 opt_UF_KeenessFactor = lookup_def_float "-funfolding-keeness-factor" (1.5::Float)
449 opt_UF_CheapOp = ( 1 :: Int) -- Only one instruction; and the args are charged for
450 opt_UF_DearOp = ( 4 :: Int)
452 opt_ReportCompile = lookUp SLIT("-freport-compile")
453 opt_NoPruneDecls = lookUp SLIT("-fno-prune-decls")
454 opt_SourceUnchanged = lookUp SLIT("-fsource-unchanged")
455 opt_Static = lookUp SLIT("-static")
456 opt_Unregisterised = lookUp SLIT("-funregisterised")
457 opt_Verbose = lookUp SLIT("-v")
459 opt_UseVanillaRegs | opt_Unregisterised = 0
460 | otherwise = mAX_Real_Vanilla_REG
461 opt_UseFloatRegs | opt_Unregisterised = 0
462 | otherwise = mAX_Real_Float_REG
463 opt_UseDoubleRegs | opt_Unregisterised = 0
464 | otherwise = mAX_Real_Double_REG
465 opt_UseLongRegs | opt_Unregisterised = 0
466 | otherwise = mAX_Real_Long_REG
470 classifyOpts :: ([CoreToDo], -- Core-to-Core processing spec
471 [StgToDo]) -- STG-to-STG processing spec
473 classifyOpts = sep argv [] [] -- accumulators...
475 sep :: [FAST_STRING] -- cmd-line opts (input)
476 -> [CoreToDo] -> [StgToDo] -- to_do accumulators
477 -> ([CoreToDo], [StgToDo]) -- result
479 sep [] core_td stg_td -- all done!
480 = (reverse core_td, reverse stg_td)
482 # define CORE_TD(to_do) sep opts (to_do:core_td) stg_td
483 # define STG_TD(to_do) sep opts core_td (to_do:stg_td)
485 sep (opt1:opts) core_td stg_td
486 = case (_UNPK_ opt1) of -- the non-"just match a string" options are at the end...
487 ',' : _ -> sep opts core_td stg_td -- it is for the parser
489 "-fsimplify" -> -- gather up SimplifierSwitches specially...
490 simpl_sep opts defaultSimplSwitches core_td stg_td
492 "-ffloat-inwards" -> CORE_TD(CoreDoFloatInwards)
493 "-ffloat-outwards" -> CORE_TD(CoreDoFloatOutwards False)
494 "-ffloat-outwards-full" -> CORE_TD(CoreDoFloatOutwards True)
495 "-fliberate-case" -> CORE_TD(CoreLiberateCase)
496 "-fcse" -> CORE_TD(CoreCSE)
497 "-fprint-core" -> CORE_TD(CoreDoPrintCore)
498 "-fstatic-args" -> CORE_TD(CoreDoStaticArgs)
499 "-fstrictness" -> CORE_TD(CoreDoStrictness)
500 "-fworker-wrapper" -> CORE_TD(CoreDoWorkerWrapper)
501 "-fspecialise" -> CORE_TD(CoreDoSpecialising)
502 "-fusagesp" -> CORE_TD(CoreDoUSPInf)
503 "-fcpr-analyse" -> CORE_TD(CoreDoCPResult)
505 "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
506 "-dstg-stats" -> STG_TD(D_stg_stats)
507 "-flambda-lift" -> STG_TD(StgDoLambdaLift)
508 "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
510 _ -> -- NB: the driver is really supposed to handle bad options
511 sep opts core_td stg_td
515 simpl_sep :: [FAST_STRING] -- cmd-line opts (input)
516 -> [SimplifierSwitch] -- simplifier-switch accumulator
517 -> [CoreToDo] -> [StgToDo] -- to_do accumulators
518 -> ([CoreToDo], [StgToDo]) -- result
520 -- "simpl_sep" tailcalls "sep" once it's seen one set
521 -- of SimplifierSwitches for a CoreDoSimplify.
524 simpl_sep input@[] simpl_sw core_td stg_td
525 = panic "simpl_sep []"
528 -- The SimplifierSwitches should be delimited by "[" and "]".
530 simpl_sep (opt1:opts) simpl_sw core_td stg_td
531 = case (_UNPK_ opt1) of
532 "[" -> simpl_sep opts simpl_sw core_td stg_td
534 this_simpl = CoreDoSimplify (isAmongSimpl simpl_sw)
536 sep opts (this_simpl : core_td) stg_td
538 opt -> case matchSimplSw opt of
539 Just sw -> simpl_sep opts (sw:simpl_sw) core_td stg_td
540 Nothing -> simpl_sep opts simpl_sw core_td stg_td
543 = firstJust [ matchSwInt opt "-fmax-simplifier-iterations" MaxSimplifierIterations
544 , matchSwInt opt "-finline-phase" SimplInlinePhase
545 , matchSwBool opt "-fno-rules" DontApplyRules
546 , matchSwBool opt "-fno-case-of-case" NoCaseOfCase
547 , matchSwBool opt "-flet-to-case" SimplLetToCase
550 matchSwBool :: String -> String -> a -> Maybe a
551 matchSwBool opt str sw | opt == str = Just sw
552 | otherwise = Nothing
554 matchSwInt :: String -> String -> (Int -> a) -> Maybe a
555 matchSwInt opt str sw = case startsWith str opt of
556 Just opt_left -> Just (sw (read opt_left))
560 %************************************************************************
562 \subsection{Switch ordering}
564 %************************************************************************
566 In spite of the @Produce*@ constructor, these things behave just like
570 instance Eq SimplifierSwitch where
571 a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
573 instance Ord SimplifierSwitch where
574 a < b = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
575 a <= b = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
578 tagOf_SimplSwitch (SimplInlinePhase _) = ILIT(1)
579 tagOf_SimplSwitch (MaxSimplifierIterations _) = ILIT(2)
580 tagOf_SimplSwitch DontApplyRules = ILIT(3)
581 tagOf_SimplSwitch SimplLetToCase = ILIT(4)
582 tagOf_SimplSwitch NoCaseOfCase = ILIT(5)
584 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
586 lAST_SIMPL_SWITCH_TAG = 5
589 %************************************************************************
591 \subsection{Switch lookup}
593 %************************************************************************
596 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
598 isAmongSimpl on_switches -- Switches mentioned later occur *earlier*
599 -- in the list; defaults right at the end.
601 tidied_on_switches = foldl rm_dups [] on_switches
602 -- The fold*l* ensures that we keep the latest switches;
603 -- ie the ones that occur earliest in the list.
605 sw_tbl :: Array Int SwitchResult
606 sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
610 all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
612 defined_elems = map mk_assoc_elem tidied_on_switches
614 -- (avoid some unboxing, bounds checking, and other horrible things:)
615 #if __GLASGOW_HASKELL__ < 405
616 case sw_tbl of { Array bounds_who_needs_'em stuff ->
618 case sw_tbl of { Array _ _ stuff ->
621 case (indexArray# stuff (tagOf_SimplSwitch switch)) of
622 #if __GLASGOW_HASKELL__ < 400
624 #elif __GLASGOW_HASKELL__ < 403
631 mk_assoc_elem k@(MaxSimplifierIterations lvl) = (IBOX(tagOf_SimplSwitch k), SwInt lvl)
632 mk_assoc_elem k@(SimplInlinePhase n) = (IBOX(tagOf_SimplSwitch k), SwInt n)
633 mk_assoc_elem k = (IBOX(tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
635 -- cannot have duplicates if we are going to use the array thing
636 rm_dups switches_so_far switch
637 = if switch `is_elem` switches_so_far
639 else switch : switches_so_far
641 sw `is_elem` [] = False
642 sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
646 Default settings for simplifier switches
649 defaultSimplSwitches = [MaxSimplifierIterations 1]
652 %************************************************************************
654 \subsection{Misc functions for command-line options}
656 %************************************************************************
660 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
662 switchIsOn lookup_fn switch
663 = case (lookup_fn switch) of
664 SwBool False -> False
667 intSwitchSet :: (switch -> SwitchResult)
671 intSwitchSet lookup_fn switch
672 = case (lookup_fn (switch (panic "intSwitchSet"))) of
673 SwInt int -> Just int
678 startsWith :: String -> String -> Maybe String
679 -- startsWith pfx (pfx++rest) = Just rest
681 startsWith [] str = Just str
682 startsWith (c:cs) (s:ss)
683 = if c /= s then Nothing else startsWith cs ss
684 startsWith _ [] = Nothing
686 endsWith :: String -> String -> Maybe String
688 = case (startsWith (reverse cs) (reverse ss)) of
690 Just rs -> Just (reverse rs)