"

 COPYRIGHT (c) 2006 by eXept Software AG

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

"{ Package: 'stx:libbasic' }"

Object subclass:#ReadEvalPrintLoop

	instanceVariableNames:'inputStream outputStream errorStream compiler prompt

		doChunkFormat traceFlag timingFlag exitAction'

	classVariableNames:''

	poolDictionaries:''

	category:'System-Support'

!

!ReadEvalPrintLoop class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 2006 by eXept Software AG

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

documentation

"

    A simple read-eval-print loop for non-GUI or stscript operation.

    A line starting with '?' shows the usage message.

    Lines starting with '#' are directives:

        #exit   - exit the rep-loop

"

! !

!ReadEvalPrintLoop methodsFor:'accessing'!

compiler:something

    compiler := something.

!

doChunkFormat

    ^ doChunkFormat ? true

    "Created: / 07-12-2006 / 18:24:04 / cg"

!

doChunkFormat:something

    doChunkFormat := something.

    "Created: / 07-12-2006 / 18:24:04 / cg"

!

error:something

    errorStream := something.

    "Created: / 07-12-2006 / 17:33:39 / cg"

!

errorStream

    ^ errorStream ? Transcript ? Stderr

    "Created: / 07-12-2006 / 19:11:56 / cg"

!

input:something

    inputStream := something.

    "Modified: / 07-12-2006 / 17:33:31 / cg"

!

inputStream

    ^ inputStream ? Stdin

    "Created: / 07-12-2006 / 19:12:13 / cg"

!

output:something

    outputStream := something.

    "Created: / 07-12-2006 / 17:27:48 / cg"

!

outputStream

    ^ outputStream ? Stdout

    "Created: / 07-12-2006 / 19:12:27 / cg"

!

prompt:something

    prompt := something.

! !

!ReadEvalPrintLoop methodsFor:'compiler interface-error handling'!

correctableError:message position:pos1 to:pos2 from:aCompiler

    "compiler notifies us of an error - ignore it"

    ^ false

!

correctableSelectorWarning:aString position:relPos to:relEndPos from:aCompiler

    "compiler notifies us of a warning - ignore it"

    ^ false

!

correctableWarning:message position:pos1 to:pos2 from:aCompiler

    "compiler notifies us of an error - ignore it"

    ^ false

    "Created: / 02-11-2010 / 13:29:22 / cg"

!

error:aString position:relPos to:relEndPos from:aCompiler

    "compiler notifies us of a warning - ignore it"

    ^ false

!

unusedVariableWarning:aString position:relPos to:relEndPos from:aCompiler

    "compiler notifies us of a warning - ignore it"

    ^ false

!

warning:aString position:relPos to:relEndPos from:aCompiler

    "compiler notifies us of a warning - ignore it"

    ^ self

! !

!ReadEvalPrintLoop methodsFor:'directives'!

cmd_clear:lineStream

    self cmd_setOrClear:lineStream to:false

    "Created: / 07-12-2006 / 19:04:50 / cg"

!

cmd_exit:lineStream

    exitAction value

    "Created: / 07-12-2006 / 18:55:46 / cg"

!

cmd_help:lineStream

    self errorStream

        nextPutAll:

'Everything entered up to an empty line is called a "chunk" and evaluated.

Lines starting with "#" are commands to the read-eval-print interpreter.

Valid commands are:

    #help ............... this text

    #exit ............... exit interpreter loop

    #use <package>....... use (load) a package

        stx:libwidg ........ GUI package

        stx:libtool ........ IDE tool package

    #show <what> ........ show info

        variables .......... interpreter variables

        processes .......... processes

        memory ............. memory usage

        flags .............. flags

    #set/clear <flag> ... set or clear a flag

        trace .............. tracing execution

        timing ............. timing execution

MiniDebugger shows its help with "?".

'

    "Created: / 07-12-2006 / 18:54:20 / cg"

!

cmd_set:lineStream

    self cmd_setOrClear:lineStream to:true

    "Modified: / 07-12-2006 / 19:04:46 / cg"

!

cmd_setOrClear:lineStream to:aBoolean

    |what|

    lineStream skipSeparators.

    what := lineStream nextAlphaNumericWord.

    (what startsWith:'tra') ifTrue:[

        traceFlag := aBoolean.

        ^ self.

    ].

    (what startsWith:'tim') ifTrue:[

        timingFlag := aBoolean.

        ^ self.

    ].

    self errorStream nextPutLine:'?? which flag ?'.

    "Modified: / 07-12-2006 / 19:13:34 / cg"

!

cmd_show:lineStream

    |what|

    lineStream skipSeparators.

    what := lineStream nextAlphaNumericWord.

    (what startsWith:'var') ifTrue:[

        ^ self.

    ].

    (what startsWith:'proc') ifTrue:[

        MiniDebugger basicNew showProcesses.

        ^ self.

    ].

    (what startsWith:'mem') ifTrue:[

        self errorStream 

            nextPutLine:('overall: ',(ObjectMemory bytesUsed // 1024) printString,' Kb');

            nextPutLine:('free   : ',(ObjectMemory freeSpace // 1024) printString,' Kb');

            nextPutLine:('minorGC: ',(ObjectMemory scavengeCount) printString);

            nextPutLine:('majorGC: ',(ObjectMemory garbageCollectCount) printString).

        ^ self.

    ].

    (what startsWith:'flag') ifTrue:[

        self errorStream 

            nextPutLine:('trace : ',traceFlag printString);

            nextPutLine:('timing: ',timingFlag printString).

        ^ self.

    ].

    self errorStream nextPutLine:'?? show what ?'.

    "Modified: / 07-12-2006 / 19:23:15 / cg"

!

cmd_use:lineStream

    |pkg|

    lineStream skipSeparators.

    pkg := lineStream upToEnd withoutSeparators.

    Smalltalk loadPackage:pkg

    "Created: / 07-12-2006 / 19:07:56 / cg"

!

directive:line

    |s cmd|

    s := line readStream.

    s next. "/ skip the hash

    s skipSeparators.

    cmd := s nextAlphaNumericWord.

    self 

        perform:('cmd_',cmd,':') asSymbol with:s 

        ifNotUnderstood:[   

            self errorStream  

                nextPutAll:'?? invalid command: ';

                nextPutAll:cmd;

                nextPutAll:'. Type "#help" for help.';

                cr.

        ].

    "Created: / 07-12-2006 / 18:49:17 / cg"

! !

!ReadEvalPrintLoop methodsFor:'evaluation'!

readEvalPrintLoop

    "{ Pragma: +optSpace }"

    "simple read-eval-print loop for non-graphical Minitalk.

     If the chunkFormat-argument is true, chunks are read.

     Otherwise, lines up to an empty line (or EOF) are read."

    exitAction := [^ self].

    ControlInterrupt handle:[:ex |

        self errorStream nextPutLine:('Cought: ', ex description).

        ex restart.

    ] do:[

        [

            |input output error lines chunk compilerClass|

            "/ re-evaluate these in the loop, so they can be changed dynamically

            input := self inputStream.

            output := self outputStream.

            error := self errorStream.

            prompt notNil ifTrue:[

                error nextPutAll:prompt.

            ].

            input atEnd ifTrue:[

                ^ self.

            ].

            self doChunkFormat ifTrue:[

                input skipSeparators.

                chunk := input nextChunk.

            ] ifFalse:[

                lines := OrderedCollection new.

                [

                    |line|

                    line := input nextLine.

                    line notEmptyOrNil ifTrue:[

                        line = '?' ifTrue:[

                            self cmd_help:nil.

                            prompt notNil ifTrue:[

                                error nextPutAll:prompt.

                            ].

                        ] ifFalse:[

                            (line startsWith:'#') ifTrue:[

                                self directive:line.

                                prompt notNil ifTrue:[

                                    error nextPutAll:prompt.

                                ].

                            ] ifFalse:[

                                lines add:line.

                            ]

                        ]

                    ].

                    line notEmptyOrNil.

                ] whileTrue.

                chunk := lines asStringWith:Character cr.

            ].

            chunk notEmptyOrNil ifTrue:[

                "abortAll is handled, but not asked for here!!"

                AbortAllOperationRequest handle:[:ex |

                    error nextPutLine:('Evaluation aborted: ', ex description)

                ] do:[ 

                    (Error, ControlInterrupt) handle:[:ex |

                        prompt isNil ifTrue:[

                            ex reject

                        ].

                        MiniDebugger enterWithMessage:(ex errorString) mayProceed:true.

                        ex mayProceed ifTrue:[

                            ex proceed.

                        ].

                        error nextPutLine:('Evaluation aborted: ', ex description).

                        ex return.

                    ] do:[

                        |value|

                        value := (compilerClass new requestor:self) evaluate:chunk compile:true.

                        value printOn:output.

                        output cr.

                    ].

                ].

            ].

        ] loop.

    ]

    "

     (ReadEvalPrintLoop new prompt:'>') readEvalPrintLoop

    "

    "Created: / 07-12-2006 / 17:27:21 / cg"

! !

!ReadEvalPrintLoop class methodsFor:'documentation'!

version

!

version_CVS

!

version_SVN

! !