Extend StreamFormatting to seperate linewrap and indenting

lib/custom_streams.gi

@@ -343,11 +343,8 @@ InstallMethod( PrintFormattingStatus, "output text custom",
 ##
 InstallMethod( SetPrintFormattingStatus, "output text custom",
  [IsOutputTextCustomRep and IsOutputTextStream,
- IsBool],
+ IsObject],
  function( str, stat)
- if stat = fail then
- Error("Print formatting status must be true or false");
- else
+ CheckValidPrintFormattingStatus(stat);
  str!.formatting := stat;
- fi;
 end);

lib/streams.gd

@@ -959,24 +959,31 @@ DeclareGlobalFunction( "InputOutputLocalProcess" );
 ## and harmless if it to passed as input to ⪆,
 ## but may be unhelpful if the output is to be passed as input to another
 ## program.
-## It is possible to turn off this behaviour for a stream using the
-## <Ref Oper="SetPrintFormattingStatus"/> operation, and to test whether it
-## is on or off using <Ref Oper="PrintFormattingStatus"/>.
+## It is possible to control this behaviour for a stream using the
+## <Ref Oper="SetPrintFormattingStatus"/> operation, and to query it
+## using <Ref Oper="PrintFormattingStatus"/>.
+## <P/>
+## The formatting status is stored in a record with two members,
+## <A>linewrap</A> and <A>indent</A>, which control if GAP wraps lines,
+## or indents, respectively. These two both take a boolean.
+## <P/>
+## For backwards compatability, all functions which control print formatting
+## will also take a boolean, which sets <A>linewrap</A> and <A>indent</A> to
+## the given boolean value.
 ## <P/>
 ## <Ref Oper="SetPrintFormattingStatus"/> sets whether output sent to the
 ## output stream <A>stream</A> via <Ref Func="PrintTo"/>,
 ## <Ref Func="AppendTo"/>, etc.
 ## will be formatted with line breaks and
-## indentation. If the second argument <A>newstatus</A> is <K>true</K>
-## then output will be so formatted, and if <K>false</K> then it will not.
-## If the stream is not a text stream, only <K>false</K> is allowed.
+## indentation. The second argument <A>newstatus</A> is a record or boolean,
+## as described above.
+## If the stream is not a text stream, both <A>linewrap</A> and <A>indent</A>
+## can only be set to <K>false</K>.
 ## <P/>
-## <Ref Oper="PrintFormattingStatus"/> returns <K>true</K> if output sent to
-## the output text stream <A>stream</A> via <Ref Func="PrintTo"/>,
-## <Ref Func="AppendTo"/>, etc.
-## will be formatted with line breaks and
-## indentation, and <K>false</K> otherwise.
-## For non-text streams, it returns <K>false</K>.
+## <Ref Oper="PrintFormattingStatus"/> returns a record containing the
+## current value of <A>linewrap</A> and <A>indent</A> for the output text
+## stream <A>stream</A>. For non-text streams, these values area always
+## both <K>false</K>.
 ## If as argument <A>stream</A> the string <C>"*stdout*"</C> is given, these
 ## functions refer to the formatting status of the standard output (so usually
 ## the user's terminal screen).<P/>
@@ -997,7 +1004,7 @@ DeclareGlobalFunction( "InputOutputLocalProcess" );
 ## gap> Print(s,"\n");
 ## [ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61,
 ## 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113 ]
-## gap> SetPrintFormattingStatus(str, false);
+## gap> SetPrintFormattingStatus(str, rec(indent:=false,linewrap:=false));
 ## gap> PrintTo(str,Primes{[1..30]});
 ## gap> s;
 ## "[ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61,\
@@ -1015,7 +1022,7 @@ DeclareGlobalFunction( "InputOutputLocalProcess" );
 ## </ManSection>
 ## <#/GAPDoc>
 ##
-DeclareOperation( "SetPrintFormattingStatus", [IsOutputStream, IsBool] );
+DeclareOperation( "SetPrintFormattingStatus", [IsOutputStream, IsObject] );
 DeclareOperation( "PrintFormattingStatus", [IsOutputStream] );
 
 
@@ -1259,3 +1266,6 @@ DeclareGlobalFunction( "InputFromUser" );
 ## <#/GAPDoc>
 ##
 DeclareGlobalFunction( "OpenExternal" );
+
+DeclareGlobalFunction( "_CheckValidPrintFormattingStatus");
+DeclareGlobalFunction( "_DefaultPrintFormattingStatus");

lib/streams.gi

@@ -860,7 +860,8 @@ function( str, append )
  Unbind(str[i]);
  od;
  fi;
- return Objectify( OutputTextStringType, [ str, true ] );
+ return Objectify( OutputTextStringType,
+ [ str, _DefaultPrintFormattingStatus() ] );
 end );
 
 
@@ -929,13 +930,9 @@ InstallMethod( PrintFormattingStatus, "output text string",
 ##
 InstallMethod( SetPrintFormattingStatus, "output text string",
  [IsOutputTextStringRep and IsOutputTextStream,
- IsBool],
+ IsObject],
  function( str, stat)
- if stat = fail then
- Error("Print formatting status must be true or false");
- else
- str![2] := stat;
- fi;
+ str![2] := _CheckValidPrintFormattingStatus(stat);
 end);
 
 
@@ -994,7 +991,8 @@ function( str, append )
  atomic OutputTextFileStillOpen do
  AddSet( OutputTextFileStillOpen, fid );
  od;
- return Objectify( OutputTextFileType, [fid, Immutable(str), true] );
+ return Objectify( OutputTextFileType,
+ [fid, Immutable(str), _DefaultPrintFormattingStatus()]);
  fi;
 end );
 
@@ -1025,7 +1023,8 @@ function( str, append )
  atomic OutputTextFileStillOpen do
  AddSet( OutputTextFileStillOpen, fid );
  od;
- return Objectify( OutputTextFileType, [fid, Immutable(str), true] );
+ return Objectify( OutputTextFileType,
+ [fid, Immutable(str), _DefaultPrintFormattingStatus() ] );
  fi;
 end );
 
@@ -1130,13 +1129,9 @@ InstallMethod( PrintFormattingStatus, "output text file",
 ##
 InstallMethod( SetPrintFormattingStatus, "output text file",
  [IsOutputTextFileRep and IsOutputTextStream,
- IsBool],
+ IsObject],
  function( str, stat)
- if stat = fail then
- Error("Print formatting status must be true or false");
- else
- str![3] := stat;
- fi;
+ str![3] := _CheckValidPrintFormattingStatus(stat);
 end);
 
 ## formatting status for stdout or current output
@@ -1151,7 +1146,7 @@ function(str)
  fi;
 end);
 
-InstallOtherMethod( SetPrintFormattingStatus, "for stdout", [IsString, IsBool],
+InstallOtherMethod( SetPrintFormattingStatus, "for stdout", [IsString, IsObject],
 function(str, status)
  if str = "*stdout*" then
  SET_PRINT_FORMATTING_STDOUT(status);
@@ -1255,9 +1250,7 @@ InstallMethod( SetPrintFormattingStatus, "output text none",
  [IsOutputTextNoneRep and IsOutputTextNone,
  IsBool],
  function( str, stat)
- if stat = fail then
- Error("Print formatting status must be true or false");
- fi;
+ _CheckValidPrintFormattingStatus(stat);
 end);
 
 
@@ -1661,7 +1654,7 @@ function ( str )
  if IsOutputTextStream( str ) then
  TryNextMethod();
  fi;
- return false;
+ return Immutable(rec(indent := false, linewrap := false) );
 end);
 
 
@@ -1676,13 +1669,45 @@ InstallMethod( SetPrintFormattingStatus, "for non-text output stream",
  TryNextMethod();
  fi;
 
- if stat = true then
- Error("non-text streams support onlyPrint formatting status false");
- elif stat = fail then
- Error("Print formatting status must be true or false");
+ stat := _CheckValidPrintFormattingStatus(stat);
+ if stat.linewrap or stat.indent then
+ Error("non-text streams do not support print formatting");
+ fi;
+end);
+
+
+InstallGlobalFunction( "_CheckValidPrintFormattingStatus",
+function(fs)
+ local r;
+ if IsBool(fs) then
+ if fs = fail then
+ Error("Formatting status cannot be 'fail'");
+ fi;
+ elif IsRecord(fs) then
+ if Set(RecNames(fs)) <> ["indent", "linewrap"] then
+ Error("Formatting status records must contain exactly two components, named 'indent' and 'linewrap'");
+ fi;
+ for r in ["indent","linewrap"] do
+ if not fs.(r) in [false, true] then
+ Error(Concatenation(r, " must be 'true' or 'false' in formatting status record"));
+ fi;
+ od;
+ else
+ Error("Formatting status must be a boolean or a record");
+ fi;
+
+ if fs = true then
+ fs := rec(indent := true, linewrap := true);
+ elif fs = false then
+ fs := rec(indent := false, linewrap := false);
  fi;
+ return Immutable(ShallowCopy(fs));
 end);
 
+InstallGlobalFunction( "_DefaultPrintFormattingStatus",
+function()
+ return Immutable(rec(linewrap := true, indent := true));
+end);
 
 #############################################################################
 ##

lib/string.gi

@@ -1405,7 +1405,7 @@ InstallGlobalFunction(StringFormatted, function(s, data...)
  fi;
  str := "";
  stream := OutputTextString(str, false);
- SetPrintFormattingStatus(stream, false);
+ SetPrintFormattingStatus(stream, rec(linewrap := false, indent := true));
 
  CallFuncList(PrintToFormatted, Concatenation([stream, s], data));
  return str;