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Mister Spy & Souheyl Bypass Shell

  
  2 Changes between GAP 4.9 and GAP 4.10
  
  This  chapter  contains an overview of the most important changes introduced
  in  GAP 4.10.0 release (the first public release of GAP 4.10). Later it will
  also contain information about subsequent update releases for GAP 4.10.
  
  These     changes     are     also     listed     on     the    Wiki    page
  https://github.com/gap-system/GAP/wiki/gap-4.10-release-notes.
  
  
  2.1 GAP 4.10.0 (November 2018)
  
  
  2.1-1 New features and major changes
  
  Reduce impact of immediate methods
        GAP  allows  declaring  so-called  immediate methods. The idea is that
        these are very simple and fast methods which are immediately called if
        information  about  an  object becomes known, in order to perform some
        quick  deduction.  For  example, if the order of a group is set, there
        might  be  immediate  methods  which  update  the filters IsFinite and
        IsTrivial of the group suitably.
  
        While this can be very elegant and useful in interactive GAP sessions,
        the  overhead  for  running these immediate methods and applying their
        results   can  become  a  major  factor  in  the  runtime  of  complex
        computations that create thousands or millions of objects.
  
        To address this, various steps were taken:
  
            some immediate methods were turned into regular methods;
  
            a   special  handlers  for  SetSize  was  created  that  deduces
              properties  which  previously  were  taken  care of by immediate
              methods;
  
            some  immediate  methods  were replaced by implications (set via
              InstallTrueMethod),  a  mechanism  that  essentially  adds  zero
              overhead, unlike immediate methods;
  
            various  group  constructors  were  modified  to  precompute and
              preset  properties  of  freshly  created group objects, to avoid
              triggering immediate methods for these.
  
        As  a  result  of  these  and  other  changes,  consider the following
        example;  with GAP 4.9, it takes about 130 seconds on one test system,
        while  with  GAP 4.10 it runs in about 22 seconds, i.e., more than six
        times faster.
  
          Example  
          G:=PcGroupCode( 741231213963541373679312045151639276850536621925972119311,11664);;
          IsomorphismGroups(G,PcGroupCode(CodePcGroup(G),Size(G)))<>fail;
        
  
        Relevant       pull       requests       and       issues:       #2386
        (https://github.com/gap-system/gap/pull/2386),                   #2387
        (https://github.com/gap-system/gap/pull/2387),                   #2522
        (https://github.com/gap-system/gap/pull/2522).
  
  Change definition of IsPGroup to not require finiteness
        This is a small change in terms of amount of code changed, but we list
        it  here  as it has a potential (albeit rather unlikely) impact on the
        code  written  by  GAP  users:  In  the past, the GAP manual entry for
        IsPGroup  defined  p-groups as being finite groups, which differs from
        the  most  commonly  used  definition  for p-groups. Note however that
        there  was not actual implication installed from IsPGroup to IsFinite,
        so  it  always was possible to actually created infinite groups in the
        filter    IsPGroup.    In    GAP   4.10,   we   adjusted   (in   #1545
        (https://github.com/gap-system/gap/pull/1545))  the  documentation for
        IsPGroup   to  the  commonly  accepted  definition  for  p-groups.  In
        addition,  code  in the GAP library and in packages using IsPGroup was
        audited  and  (in  a  very  few  cases)  adjusted  to explicitly check
        IsFinite                 (see                e.g.                #2866
        (https://github.com/gap-system/gap/pull/2866)).
  
  Experimental support for using the Julia garbage collector
        It  is now possible to use the garbage collector of the Julia language
        (https://julialang.org)  instead  of  GAP's traditional GASMAN garbage
        collector.  This  is  partly  motivated  by  a  desire  to allow tight
        integration with GAP and Julia in the future. Warning: right now, this
        is slower, and also requires a patched version of Julia.
  
        Relevant               pull               requests:              #2092
        (https://github.com/gap-system/gap/pull/2092),                   #2408
        (https://github.com/gap-system/gap/pull/2408),                   #2461
        (https://github.com/gap-system/gap/pull/2461),                   #2485
        (https://github.com/gap-system/gap/pull/2485),                   #2495
        (https://github.com/gap-system/gap/pull/2495),                   #2672
        (https://github.com/gap-system/gap/pull/2672),                   #2688
        (https://github.com/gap-system/gap/pull/2688),                   #2793
        (https://github.com/gap-system/gap/pull/2793),                   #2904
        (https://github.com/gap-system/gap/pull/2904),                   #2905
        (https://github.com/gap-system/gap/pull/2905),                   #2931
        (https://github.com/gap-system/gap/pull/2931).
  
  libGAP (work in progress)
        We  now provide a experimental way to allow 3rd party code to link GAP
        as   a  library;  this  is  based  on  the  libGAP  code  by  SageMath
        (https://www.sagemath.org), but different: while we aim to provide the
        same  functionality,  we  do  not  rename  any  symbols, and we do not
        provide  the  same  API. We hope that a future version of SageMath can
        drop  its custom modifications for GAP and use this interface instead.
        Work  is  underway to achieve this goal. If you are interested in this
        kind  of interface, please get in touch with us to help us improve it.
        See                  also                  this                  email
        (https://mail.gap-system.org/pipermail/gap/2018-August/001123.html).
  
        To  get an idea how libGAP works, you can configure GAP as normal, and
        then  execute  make  testlibgap  which will build a small program that
        uses some of the existing API and links GAP. Relevant pull requests:
  
            #1690    (https://github.com/gap-system/gap/pull/1690)   Add   a
              callback to FuncJUMP_TO_CATCH
  
            #2528 (https://github.com/gap-system/gap/pull/2528) Add IsLIBGAP
              constant
  
            #2702   (https://github.com/gap-system/gap/pull/2702)   Add  GAP
              kernel API
  
            #2723   (https://github.com/gap-system/gap/pull/2723)  Introduce
              command line options --norepl and --nointeract
  
  
  2.1-2 Improved and extended functionality
  
      #2041        (https://github.com/gap-system/gap/pull/2041)       Teach
        FrattiniSubgroup methods to check for solvability
  
      #2053 (https://github.com/gap-system/gap/pull/2053) Faster computation
        of modular inverses of integers
  
      #2057  (https://github.com/gap-system/gap/pull/2057)  Various changes,
        including:
  
            Improve  computation  of  automorphism  groups for fp groups (we
              still  recommend  to  instead  first  convert  the  group  to  a
              computationally nice representation, such as a perm or pc group)
  
            Add         MinimalFaithfulPermutationDegree         (Reference:
              MinimalFaithfulPermutationDegree) attribute for finite groups
  
            Improve performance of GQuotients(F,G) when F is an fp group
  
            Some other performance and documentation tweaks
  
      #2061       (https://github.com/gap-system/gap/pull/2061),       #2086
        (https://github.com/gap-system/gap/pull/2086),                   #2159
        (https://github.com/gap-system/gap/pull/2159),                   #2306
        (https://github.com/gap-system/gap/pull/2306) Speed up GcdInt, LcmInt,
        PValuation, RootInt, SmallestRootInt, IsPrimePowerInt
  
      #2063  (https://github.com/gap-system/gap/pull/2063)  Teach  GAP  that
        BPSW  pseudo  primes  less  than  2^64  are all known to be prime (the
        previous limit was 10^13)
  
      #2091      (https://github.com/gap-system/gap/pull/2091)      Refactor
        DeclareAttribute   and   NewAttribute   (arguments  are  now  verified
        stricter)
  
      #2115       (https://github.com/gap-system/gap/pull/2115),       #2204
        (https://github.com/gap-system/gap/pull/2204),                   #2272
        (https://github.com/gap-system/gap/pull/2272)    Allow    (optionally)
        passing  a  random source to many more Random methods than before, and
        also to RandomList
  
      #2136   (https://github.com/gap-system/gap/pull/2136)   Add  shortname
        entry to record returned by IsomorphismTypeInfoFiniteSimpleGroup
  
      #2181      (https://github.com/gap-system/gap/pull/2181)     Implement
        Union(X,Y),    where    X    and    Y    are    in   PositiveIntegers,
        NonnegativeIntegers,     Integers,     GaussianIntegers,    Rationals,
        GaussianRationals,  Cyclotomics,  at  least  where  a  suitable output
        object exists (we already provided Intersection(X,Y) for a long time)
  
      #2185      (https://github.com/gap-system/gap/pull/2185)     Implement
        IsCentral(M,x), where M is a magma, monoid, group, ring, algebra, etc.
        and  x  an  element of M (the documentation already claimed that these
        exist for a long time)
  
      #2199      (https://github.com/gap-system/gap/pull/2199)      Optimize
        true/false conditions when coding if-statements
  
      #2200         (https://github.com/gap-system/gap/pull/2200)        Add
        StringFormatted     (Reference:    StringFormatted),    PrintFormatted
        (Reference:      PrintFormatted),     PrintToFormatted     (Reference:
        PrintToFormatted)
  
      #2222    (https://github.com/gap-system/gap/pull/2222)   Turn   hidden
        implications into actual implications
  
      #2223   (https://github.com/gap-system/gap/pull/2223)   Add  operation
        PositionsBound  (Reference:  PositionsBound)  which returns the set of
        all bound positions in a given list
  
      #2224       (https://github.com/gap-system/gap/pull/2224),       #2243
        (https://github.com/gap-system/gap/pull/2243),                   #2340
        (https://github.com/gap-system/gap/pull/2340)                  Improve
        ShowImpliedFilters output
  
      #2225       (https://github.com/gap-system/gap/pull/2225)      Improve
        LocationFunc for kernel function
  
      #2232  (https://github.com/gap-system/gap/pull/2232)  Make ValueGlobal
        faster
  
      #2242    (https://github.com/gap-system/gap/pull/2242)    Add   global
        function CycleFromList (Reference: CycleFromList)
  
      #2244 (https://github.com/gap-system/gap/pull/2244) Make rank argument
        to InstallImmediateMethod optional, similar to InstallMethod
  
      #2274   (https://github.com/gap-system/gap/pull/2274)  Ensure  uniform
        printing  of  machine floats nan, inf, -inf across different operating
        systems
  
      #2287        (https://github.com/gap-system/gap/pull/2287)        Turn
        IsInfiniteAbelianizationGroup   into   a   property   and   add   some
        implications involving it
  
      #2293       (https://github.com/gap-system/gap/pull/2293),       #2602
        (https://github.com/gap-system/gap/pull/2602),                   #2718
        (https://github.com/gap-system/gap/pull/2718)  Improved and documented
        various  kernel  and memory debugging facilities (requires recompiling
        GAP       with       --enable-debug,      --enable-valgrind      resp.
        --enable-memory-checking)
  
      #2308  (https://github.com/gap-system/gap/pull/2308)  Method selection
        code was rewritten from GAP to C
  
      #2326 (https://github.com/gap-system/gap/pull/2326) Change SimpleGroup
        to  perform  better  input  validation  and  improve  or correct error
        message for type 2E
  
      #2375  (https://github.com/gap-system/gap/pull/2375)  Make  last2  and
        last3 available in break loops
  
      #2383 (https://github.com/gap-system/gap/pull/2383) Speed improvements
        for automorphism groups
  
      #2393  (https://github.com/gap-system/gap/pull/2393) Track location of
        InstallMethod and InstallImmediateMethod
  
      #2422  (https://github.com/gap-system/gap/pull/2422)  Improve tracking
        of InstallMethod and DeclareOperation
  
      #2426     (https://github.com/gap-system/gap/pull/2426)    Speed    up
        InverseMatMod with integer modulus
  
      #2427  (https://github.com/gap-system/gap/pull/2427)  Fix and complete
        support for custom functions (i.e., objects which can be called like a
        function using obj(arg) syntax)
  
      #2456  (https://github.com/gap-system/gap/pull/2456)  Add  PrintString
        and ViewString methods for character tables
  
      #2474       (https://github.com/gap-system/gap/pull/2474)       Change
        IsConstantRationalFunction  and IsUnivariateRationalFunction to return
        false if input isn't a rational function (instead of an error)
  
      #2474  (https://github.com/gap-system/gap/pull/2474)  Add  methods for
        multiplying rational functions over arbitrary rings by rationals
  
      #2496   (https://github.com/gap-system/gap/pull/2496)   Finite  groups
        whose  order is known and not divisible by 4 are immediately marked as
        solvable
  
      #2509  (https://github.com/gap-system/gap/pull/2509)  Rewrite  support
        for .gz compressed files to use zlib, now works on Windows
  
      #2519       (https://github.com/gap-system/gap/pull/2519),       #2524
        (https://github.com/gap-system/gap/pull/2524),                   #2531
        (https://github.com/gap-system/gap/pull/2531)  Test  now rejects empty
        inputs and warns if the input contains no test
  
      #2574   (https://github.com/gap-system/gap/pull/2574)  When  reporting
        syntax  errors,  GAP  now underlines the complete last token, not just
        the position where it stopped parsing
  
      #2577       (https://github.com/gap-system/gap/pull/2577),       #2613
        (https://github.com/gap-system/gap/pull/2613)    Add   quadratic   and
        bilinear add forms for Omega(e,d,q)
  
      #2598 (https://github.com/gap-system/gap/pull/2598) Add BannerFunction
        to PackageInfo.g
  
      #2606 (https://github.com/gap-system/gap/pull/2606) Improve PageSource
        to  work  on  functions that were read from a file given by a relative
        path
  
      #2616     (https://github.com/gap-system/gap/pull/2616)    Speed    up
        computation  of  quotients of associative words by using existing (but
        previously unused) kernel functions for that
  
      #2640  (https://github.com/gap-system/gap/pull/2640) Work on MatrixObj
        and VectorObj
  
      #2654 (https://github.com/gap-system/gap/pull/2654) Make Sortex stable
  
      #2666       (https://github.com/gap-system/gap/pull/2666),       #2686
        (https://github.com/gap-system/gap/pull/2686)  Add IsBiCoset attribute
        for  right  cosets,  which  is  true if the right coset is also a left
        coset
  
      #2684         (https://github.com/gap-system/gap/pull/2684)        Add
        NormalSubgroups  methods  for  symmetric  and  alternating permutation
        groups
  
      #2726      (https://github.com/gap-system/gap/pull/2726)      Validate
        PackageInfo.g when loading packages
  
      #2733  (https://github.com/gap-system/gap/pull/2733) Minor performance
        improvements, code cleanup and very local fixes
  
      #2750    (https://github.com/gap-system/gap/pull/2750)   Reject   some
        invalid uses of ~
  
      #2812   (https://github.com/gap-system/gap/pull/2812)   Reduce  memory
        usage  and  improve  performance  the MTC (modified Todd-Coxeter) code
        that  was rewritten in GAP 4.9, but which was much slower than the old
        (but buggy) code it replaced; the difference is now small, but the old
        code still is faster in some case.
  
      #2855       (https://github.com/gap-system/gap/pull/2855),       #2877
        (https://github.com/gap-system/gap/pull/2877)    Add   IsPackageLoaded
        (Reference: IsPackageLoaded)
  
      #2878 (https://github.com/gap-system/gap/pull/2878) Speed up conjugacy
        tests  for  permutation  by  using  random  permutation of points when
        selecting base in centraliser
  
      #2899    (https://github.com/gap-system/gap/pull/2899)   TestDirectory
        reports number of failures and failed files
  
  
  2.1-3 Changed documentation
  
      #2192 (https://github.com/gap-system/gap/pull/2192) Add an example for
        PRump (Reference: PRump)
  
      #2219  (https://github.com/gap-system/gap/pull/2219)  Add  examples to
        the relations chapter (see 'Reference: Relations').
  
      #2360      (https://github.com/gap-system/gap/pull/2360)      Document
        IdealDecompositionsOfPolynomial                            (Reference:
        IdealDecompositionsOfPolynomial)  (also  accessible  via  its  synonym
        DecomPoly) and NormalizerViaRadical (Reference: NormalizerViaRadical)
  
      #2366  (https://github.com/gap-system/gap/pull/2366)  Do not recommend
        avoiding   X   which   is  a  synonym  for  Indeterminate  (Reference:
        Indeterminate)
  
      #2432  (https://github.com/gap-system/gap/pull/2432)  Correct  a claim
        about the index of Omega(e,p,q) in SO(e,p,q) (see SO (Reference: SO))
  
      #2549       (https://github.com/gap-system/gap/pull/2549)       Update
        documentation  of  the -T command line option (see 'Reference: Command
        Line Options')
  
      #2551  (https://github.com/gap-system/gap/pull/2551)  Add  new command
        line  option  --alwaystrace which ensures error backtraces are printed
        even  if  break  loops  are  disabled  (see  'Reference:  Command Line
        Options')
  
      #2681     (https://github.com/gap-system/gap/pull/2681)     Documented
        ClassPositionsOfSolvableRadical                            (Reference:
        ClassPositionsOfSolvableRadical)   and  CharacterTableOfNormalSubgroup
        (Reference: CharacterTableOfNormalSubgroup)
  
      #2834   (https://github.com/gap-system/gap/pull/2834)  Improve  manual
        section about Info classes (see 'Reference: Info Functions')
  
  
  2.1-4 Fixed bugs that could lead to crashes
  
      #2154       (https://github.com/gap-system/gap/pull/2154),       #2242
        (https://github.com/gap-system/gap/pull/2242),                   #2294
        (https://github.com/gap-system/gap/pull/2294),                   #2344
        (https://github.com/gap-system/gap/pull/2344),                   #2353
        (https://github.com/gap-system/gap/pull/2353),                   #2736
        (https://github.com/gap-system/gap/pull/2736)  Fix  several  potential
        (albeit rare) crashes related to garbage collection
  
      #2196   (https://github.com/gap-system/gap/pull/2196)   Fix  crash  in
        HasKeyBag on SPARC Solaris 11
  
      #2305   (https://github.com/gap-system/gap/pull/2305)   Fix  crash  in
        PartialPerm([1,2,8],[3,4,1,2]);
  
      #2477  (https://github.com/gap-system/gap/pull/2477) Fix crash if ~ is
        used to modify list
  
      #2499  (https://github.com/gap-system/gap/pull/2499)  Fix crash in the
        kernel functions {8,16,32}Bits_ExponentSums3
  
      #2601   (https://github.com/gap-system/gap/pull/2601)   Fix  crash  in
        MakeImmutable(rec(x:=~));
  
      #2665  (https://github.com/gap-system/gap/pull/2665) Fix crash when an
        empty filename is passed
  
      #2711  (https://github.com/gap-system/gap/pull/2711)  Fix  crash  when
        tracing buggy attribute/property methods that fail to return a value
  
      #2766    (https://github.com/gap-system/gap/pull/2766)   Fix   obscure
        crashes by using a!{l} syntax inside a function (this syntax never was
        fully implemented and was unusable, and now has been removed)
  
  
  2.1-5 Fixed bugs that could lead to incorrect results
  
      #2085   (https://github.com/gap-system/gap/pull/2085)   Fix   bugs  in
        JenningsLieAlgebra  and  PCentralLieAlgebra  that  could  e.g. lead to
        incorrect LieLowerCentralSeries results
  
      #2113 (https://github.com/gap-system/gap/pull/2113) Fix IsMonomial for
        reducible characters and some related improvements
  
      #2183   (https://github.com/gap-system/gap/pull/2183)   Fix   bug   in
        ValueMolienSeries  that could lead to ValueMolienSeries(m,0) not being
        1
  
      #2198        (https://github.com/gap-system/gap/pull/2198)        Make
        multiplication of larger integers by tiny floats commutative (e.g. now
        10.^-300  *  10^400  and  10^400  * 10.^-300 both give infinity, while
        before  10^400  *  10.^-300 gave 1.e+100); also ensure various strange
        inputs,  like  rec()^1;,  produce an error (instead of setting a^1 = a
        and 1*a = a for almost any kind of object)
  
      #2273         (https://github.com/gap-system/gap/pull/2273)        Fix
        TypeOfOperation for setters of and-filters
  
      #2275       (https://github.com/gap-system/gap/pull/2275),       #2280
        (https://github.com/gap-system/gap/pull/2280)                      Fix
        IsFinitelyGeneratedGroup    and   IsFinitelyGeneratedMonoid   to   not
        (incorrectly) assume that a given infinite generating set implies that
        there is no finite generating set
  
      #2311   (https://github.com/gap-system/gap/pull/2311)   Do   not   set
        IsFinitelyGeneratedGroup  for  finitely generated magmas which are not
        groups
  
      #2452   (https://github.com/gap-system/gap/pull/2452)   Fix  bug  that
        allowed   creating   empty   magmas   in  the  filters  IsTrivial  and
        IsMagmaWithInverses
  
      #2689  (https://github.com/gap-system/gap/pull/2689) Fix LogFFE to not
        return negative results on 32 bit systems
  
      #2766  (https://github.com/gap-system/gap/pull/2766)  Fix  a  bug that
        allowed creating corrupt permutations
  
  
  2.1-6 Fixed bugs that could lead to break loops
  
      #2040  (https://github.com/gap-system/gap/pull/2040)  Raise  error  if
        eager     float     literal     conversion    fails    (fixes    #1105
        (https://github.com/gap-system/gap/pull/1105))
  
      #2582         (https://github.com/gap-system/gap/pull/2582)        Fix
        ExtendedVectors for trivial vector spaces
  
      #2617         (https://github.com/gap-system/gap/pull/2617)        Fix
        HighestWeightModule for Lie algebras in certain cases
  
      #2829  (https://github.com/gap-system/gap/pull/2829)  Fix  ShallowCopy
        for IteratorOfCartesianProduct
  
  
  2.1-7 Other fixed bugs
  
      #2220   (https://github.com/gap-system/gap/pull/2220)   Do   not   set
        IsSubsetLocallyFiniteGroup filter for finite fields
  
      #2268  (https://github.com/gap-system/gap/pull/2268)  Handle spaces in
        filenames of gzipped filenames
  
      #2269       (https://github.com/gap-system/gap/pull/2269),       #2660
        (https://github.com/gap-system/gap/pull/2660) Fix some issues with the
        interface between GAP and XGAP (or other similar frontends for GAP)
  
      #2315  (https://github.com/gap-system/gap/pull/2315)  Prevent creation
        of  groups  of  floats,  just  like  we  prevent creation of groups of
        cyclotomics
  
      #2350  (https://github.com/gap-system/gap/pull/2350)  Fix prompt after
        line continuation
  
      #2365  (https://github.com/gap-system/gap/pull/2365)  Fix  tracing  of
        mutable variants of One/Zero/Inv/AInv
  
      #2398 (https://github.com/gap-system/gap/pull/2398) Fix PositionStream
        to report correct position
  
      #2467  (https://github.com/gap-system/gap/pull/2467)  Fix  support for
        identifiers of length 1023 and more
  
      #2470  (https://github.com/gap-system/gap/pull/2470)  Do  not  display
        garbage after certain syntax error messages
  
      #2533  (https://github.com/gap-system/gap/pull/2533)  Fix  composing a
        map with an identity map to not produce a range that is too big
  
      #2638   (https://github.com/gap-system/gap/pull/2638)  Fix  result  of
        Random  on  64  bit big endian system to match those on little endian,
        and on 32 bit big endian
  
      #2672  (https://github.com/gap-system/gap/pull/2672) Fix MakeImmutable
        for  weak  pointer objects, which previously failed to make subobjects
        immutable
  
      #2674  (https://github.com/gap-system/gap/pull/2674) Fix SaveWorkspace
        to return false in case of an error, and true only if successful
  
      #2681  (https://github.com/gap-system/gap/pull/2681)  Fix  Display for
        the character table of a trivial group
  
      #2716  (https://github.com/gap-system/gap/pull/2716)  When  seeding  a
        Mersenne  twister  from a string, the last few characters would not be
        used  if  the  string  length was not a multiple of 4. Fixing this may
        lead to different series of random numbers being generated.
  
      #2720  (https://github.com/gap-system/gap/pull/2720) Reject workspaces
        made  in a GAP with readline support in a GAP without, and vice versa,
        instead of crashing
  
      #2657  (https://github.com/gap-system/gap/pull/2657) The subobjects of
        the   mutable   values   of   the   attributes   ComputedClassFusions,
        ComputedIndicators,  ComputedPowerMaps,  ComputedPrimeBlockss  are now
        immutable.  This  makes  sure  that  the  values  are not accidentally
        changed. This change may have side-effects in users' code, for example
        the  object  returned by 0 * ComputedPowerMaps( CharacterTable( "A5" )
        )[2]  had  been  a mutable list before the change, and is an immutable
        list from now on.
  
  
  2.1-8 Removed or obsolete functionality
  
      Remove  multiple  undocumented  internal functions. Nobody should have
        been  using  them, but if you were, you may extract it from a previous
        GAP      release      that      still     contained     it.     (#2670
        (https://github.com/gap-system/gap/pull/2670),                   #2781
        (https://github.com/gap-system/gap/pull/2781) and more)
  
      #2335   (https://github.com/gap-system/gap/pull/2335)  Remove  several
        functions  and  variables  that  were  deprecated  for  a  long  time:
        DiagonalizeIntMatNormDriven,              DeclarePackageDocumentation,
        KERNEL_VERSION,  GAP_ROOT_PATHS,  LOADED_PACKAGES,  PACKAGES_VERSIONS,
        IsTuple,      StateRandom,      RestoreStateRandom,      StatusRandom,
        FactorCosetOperation,        ShrinkCoeffs,        ExcludeFromAutoload,
        CharacterTableDisplayPrintLegendDefault,
        ConnectGroupAndCharacterTable,               IsSemilatticeAsSemigroup,
        CreateCompletionFiles, PositionFirstComponent, ViewLength
  
      #2502   (https://github.com/gap-system/gap/pull/2502)  Various  kernel
        functions  now  validate their inputs more carefully (making it harder
        to produce bad effects by accidentally passing bad data to them)
  
      #2700       (https://github.com/gap-system/gap/pull/2700)       Forbid
        constructors with 0 arguments (they were never meaningful)
  
  
  2.1-9 Packages
  
  GAP 4.10.0 distribution includes 140 packages.
  
  Added to the distribution:
  
      The  francy  package by Manuel Martins, which provides an interface to
        draw  graphics  using  objects.  This  interface  allows  creation  of
        directed  and  undirected  graphs,  trees, line charts, bar charts and
        scatter charts. These graphical objects are drawn inside a canvas that
        includes a space for menus and to display informative messages. Within
        the  canvas  it  is possible to interact with the graphical objects by
        clicking, selecting, dragging and zooming.
  
      The  JupyterVis package by Nathan Carter, which is intended for use in
        Jupyter Notebooks running GAP kernels and adds visualization tools for
        use in such notebooks, such as charts and graphs.
  
  No longer redistributed with GAP:
  
      The  linboxing  package  has  been  unusable (it does not compile) for
        several  years now, and is unmaintained. It was therefore dropped from
        the  GAP  package distribution. If anybody is willing to take over and
        fix    the    package,   the   latest   sources   are   available   at
        https://github.com/gap-packages/linboxing.
  
      The  recogbase  package  has  been  merged into the recog package, and
        therefore is no longer distributed with GAP.
  
  
  2.2 GAP 4.10.1 (February 2019)
  
  
  2.2-1 Changes in the core GAP system introduced in GAP 4.10.1
  
  Fixes  in  the  experimental  way  to  allow 3rd party code to link GAP as a
  library:
  
      Do  not start a session when loading workspace if --nointeract command
        line            option            is            used            (#2840
        (https://github.com/gap-system/gap/pull/2840)).
  
      Add    prototype   for   GAP_Enter   and   GAP_Leave   macros   (#3096
        (https://github.com/gap-system/gap/pull/3096)).
  
      Prevent infinite recursions in echoandcheck and SyWriteandcheck (#3102
        (https://github.com/gap-system/gap/pull/3102)).
  
      Remove      environ      arguments      and      sysenviron     (#3111
        (https://github.com/gap-system/gap/pull/3111)).
  
  Fixes in the experimental support for using the Julia garbage collector:
  
      Fix      task     scanning     for     the     Julia     GC     (#2969
        (https://github.com/gap-system/gap/pull/2969)).
  
      Fix      stack     marking     for     the     Julia     GC     (#3199
        (https://github.com/gap-system/gap/pull/3199)).
  
      Specify   the   Julia  binary  instead  of  the  Julia  prefix  (#3243
        (https://github.com/gap-system/gap/pull/3243)).
  
      Export   Julia   CFLAGS,  LDFLAGS,  and  LIBS  to  sysinfo.gap  (#3248
        (https://github.com/gap-system/gap/pull/3248)).
  
      Change  MPtr Julia type of GAP objects to be a subtype of the abstract
        Julia  GapObj  type  provided  by the Julia package GAPTypes.jl (#3497
        (https://github.com/gap-system/gap/pull/3497)).
  
  Improved and extended functionality:
  
      Always  generate sysinfo.gap (previously, it was only generated if the
        "compatibility   mode"   of  the  build  system  was  enabled)  (#3042
        (https://github.com/gap-system/gap/pull/3042)).
  
      Add  support  for  writing  to  ERROR_OUTPUT  from  kernel code (#3043
        (https://github.com/gap-system/gap/pull/3043)).
  
      Add make check (#3285 (https://github.com/gap-system/gap/pull/3285)).
  
  Changed documentation:
  
      Fix  documentation  of  NumberFFVector (Reference: NumberFFVector) and
        add an example (#3079 (https://github.com/gap-system/gap/pull/3079)).
  
  Fixed bugs that could lead to crashes:
  
      Fix     readline     crash     when     using     autocomplete    with
        colored-completion-prefix     turned     on     in     Bash     (#2991
        (https://github.com/gap-system/gap/pull/2991)).
  
      Fix       overlapping      memcpy      in      APPEND_LIST      (#3216
        (https://github.com/gap-system/gap/pull/3216)).
  
  Fixed bugs that could lead to incorrect results:
  
      Fix    bugs    in   the   code   for   partial   permutations   (#3220
        (https://github.com/gap-system/gap/pull/3220)).
  
      Fix  a  bug  in Gcd for polynomials not returning standard associates,
        introduced           in           GAP           4.10.0          (#3227
        (https://github.com/gap-system/gap/pull/3227)).
  
  Fixed bugs that could lead to break loops:
  
      Change  GroupWithGenerators (Reference: GroupWithGenerators) to accept
        collections  again  (to  avoid regressions in code that relied on this
        undocumented                      behavior)                     (#3095
        (https://github.com/gap-system/gap/pull/3095)).
  
      Fix  ShallowCopy  (Reference:  ShallowCopy)  for  for  a  Knuth-Bendix
        rewriting                         system                        (#3128
        (https://github.com/gap-system/gap/pull/3128)).   [Reported  by  Ignat
        Soroko]
  
      Fix   IsMonomialMatrix  (Reference:  IsMonomialMatrix)  to  work  with
        compressed                       matrices                       (#3149
        (https://github.com/gap-system/gap/pull/3149)).  [Reported  by Dominik
        Bernhardt]
  
  Removed or obsolete functionality:
  
      Disable  make  install  (previously it displayed a warning which often
        got ignored) (#3005 (https://github.com/gap-system/gap/pull/3005)).
  
  Other fixed bugs:
  
      Fix   some  errors  which  stopped  triggering  a  break  loop  (#3013
        (https://github.com/gap-system/gap/pull/3013)).
  
      Fix      compiler      error      with      GCC      4.4.7      (#3026
        (https://github.com/gap-system/gap/pull/3026)).
  
      Fix           string           copying           logic          (#3071
        (https://github.com/gap-system/gap/pull/3071)).
  
  
  2.2-2 New and updated packages since GAP 4.10.0
  
  GAP 4.10.1 distribution contains 145 packages, including updated versions of
  35  packages  from  GAP 4.10.0 distribution, and also the following five new
  packages:
  
      MajoranaAlgebras  by  Markus  Pfeiffer  and  Madeleine  Whybrow, which
        constructs Majorana representations of finite groups.
  
      PackageManager  by Michael Torpey, providing a collection of functions
        for  installing  and  removing  GAP packages, with the eventual aim of
        becoming a full pip-style package manager for the GAP system.
  
      Thelma  by  Victor  Bovdi  and Vasyl Laver, implementing algorithms to
        deal with threshold elements.
  
      walrus by Markus Pfeiffer, providing methods for proving hyperbolicity
        of finitely presented groups in polynomial time.
  
      YangBaxter   by  Leandro  Vendramin  and  Alexander  Konovalov,  which
        provides  functionality  to  construct  classical and skew braces, and
        also includes a database of classical and skew braces of small orders.
  
  
  2.3 GAP 4.10.2 (June 2019)
  
  
  2.3-1 Changes in the core GAP system introduced in GAP 4.10.21
  
  Improvements  in the experimental way to allow 3rd party code to link GAP as
  a library:
  
      Add GAP_AssignGlobalVariable and GAP_IsNameOfWritableGlobalVariable to
        the libGAP API (#3438 (https://github.com/gap-system/gap/pull/3438)).
  
  Fixes in the experimental support for using the Julia garbage collector:
  
      Fix of a problem where the Julia GC during a partial sweep frees some,
        but  not  all  objects  of an unreachable data structure, and also may
        erroneously    try    to   mark   the   deallocated   objects   (#3412
        (https://github.com/gap-system/gap/pull/3412)).
  
      Fix  stack  scanning  for  the  Julia GC when GAP is used as a library
        (#3432 (https://github.com/gap-system/gap/pull/3432)).
  
  Fixed bugs that could lead to crashes:
  
      Fix a bug in TransformationListList (Reference: TransformationListList
        for  a  source  and  destination)  which  could  cause  a crash (#3463
        (https://github.com/gap-system/gap/pull/3463)).
  
  Fixed bugs that could lead to incorrect results:
  
      Fix    a   bug   in   ClassPositionsOfLowerCentralSeries   (Reference:
        ClassPositionsOfLowerCentralSeries).  [Reported  by  Frieder  Ladisch]
        (#3321 (https://github.com/gap-system/gap/pull/3321)).
  
      Fix  a  dangerous  bug  in  the comparison of large negative integers,
        introduced  in  GAP  4.10.1: if x and y were equal, but not identical,
        large  negative  numbers  then  x  < y returned true instead of false.
        (#3478 (https://github.com/gap-system/gap/pull/3478)).
  
  Fixed bugs that could lead to break loops:
  
      If   the   group   has  been  obtained  as  subgroup  from  a  Fitting
        free/solvable radical computation, the data is inherited and might not
        guarantee  that the factor group really is Fitting free. Added a check
        and     an     assertion    to    catch    this    situation    (#3154
        (https://github.com/gap-system/gap/pull/3154)).
  
      Fix    declaration    of    sparse    action    homomorphisms   (#3281
        (https://github.com/gap-system/gap/pull/3281)).
  
      LatticeViaRadical       called      ClosureSubgroupNC      (Reference:
        ClosureSubgroupNC)  assuming that the parent contained all generators.
        It  now  calls  ClosureSubgroup  (Reference: ClosureSubgroup) instead,
        since  this  can  not  be  always  guaranteed  (this could happen, for
        example,  in perfect subgroup computation). Also added an assertion to
        ClosureSubgroupNC   (Reference:   ClosureSubgroupNC)   to  catch  this
        situation   in   other   cases.   [Reported   by  Serge  Bouc]  (#3397
        (https://github.com/gap-system/gap/pull/3397)).
  
      Fix  a  "method  not  found"  error  in  SubdirectProduct  (Reference:
        SubdirectProduct)                                               (#3485
        (https://github.com/gap-system/gap/pull/3485)).
  
  Other fixed bugs:
  
      Fix  corner  case  in  modified Todd-Coxeter algorithm when relator is
        trivial (#3311 (https://github.com/gap-system/gap/pull/3311)).
  
  
  2.3-2 New and updated packages since GAP 4.10.1
  
  GAP 4.10.1 distribution contains 145 packages, including updated versions of
  55 packages from GAP 4.10.1 distribution,
  
  A  new  package MonoidalCategories by Mohamed Barakat, Sebastian Gutsche and
  Sebastian  Posur have been added to the distribution. It is based on the CAP
  package and implements monoidal structures for CAP.
  
  Unfortunately  we had to withdraw the QaoS package from distribution of GAP,
  as  the  servers  it  crucially  relies  on  for its functionality have been
  permanently   retired   some   time   ago  and  are  not  coming  back  (see
  https://github.com/gap-packages/qaos/issues/13 for details).