The Inbox: Compiler.quasiquote-eem.248.mcz

A new version of Compiler was added to project The Inbox:
http://source.squeak.org/inbox/Compiler.quasiquote-eem.248.mcz

==================== Summary ====================

Name: Compiler.quasiquote-eem.248
Author: eem
Time: 5 February 2013, 9:54:20.317 pm
UUID: ef044906-3339-48cc-856b-9b5172e3e81b
Ancestors: Compiler-cwp.247

Add a quasi-quote form that allows convenient embedding
of substrings within a format string, and provides a
convenient way of embedding literal strings within an
alternative literal string whose string delimiter is different.

e.g.
        `hello [#cruel] world!`
evaluates to
        'hello cruel world'.

        `S1[B1]...SN[BN]SN+1`

is equivalent to
        { 'S1'. [B1] value. ... 'SN'. [BN] value. 'SN+1' } concatenateQuasiQuote
where concatenateQuasiQuote sends asString to each
element and answers the concatenation of those elements.

however, single-statement blocks are inlined, so e.g. the
above `hello [#cruel] world!` is compiled as
        { 'hello '. #cruel. ' world!' } concatenateQuasiQuote

See Tests.quasiquote-eem.188 for tests and examples.

=============== Diff against Compiler-cwp.247 ===============

Item was added:
+ ----- Method: Array>>concatenateQuasiQuote (in category '*Compiler-support') -----
+ concatenateQuasiQuote
+ "This method is used in compilation of quasi-quote constructs.
+ It MUST NOT be deleted or altered."
+
+ | s sz |
+ sz := self size.
+ s := WriteStream on: (String new: sz * 16).
+ 1 to: sz do:
+ [:i| s nextPutAll: (self at: i) asString].
+ ^s contents!

Item was removed:
- ----- Method: Decompiler>>checkForBlock:selector:arguments: (in category 'control') -----
- checkForBlock: receiver selector: selector arguments: arguments
- selector == #blockCopy: ifTrue:
- [^self checkForBlockCopy: receiver].
- self assert: selector == #closureCopy:copiedValues:.
- ^self checkForClosureCopy: receiver arguments: arguments!

Item was added:
+ ----- Method: Decompiler>>checkForMacroMessage:selector:arguments: (in category 'control') -----
+ checkForMacroMessage: rcvr selector: selector arguments: args
+ ^ (selector == #concatenateQuasiQuote
+   and: [self checkForQuasiQuote: rcvr selector: selector arguments: args])
+  or: [(#closureCopy:copiedValues: == selector
+   and: [self checkForClosureCopy: rcvr arguments: args])
+  or: [#blockCopy: == selector
+  and: [self checkForBlockCopy: rcvr]]]!

Item was added:
+ ----- Method: Decompiler>>checkForQuasiQuote:selector:arguments: (in category 'control') -----
+ checkForQuasiQuote: rcvr "<BraceNode>" selector: selector "<Symbol>" arguments: args "<Array>"
+ stack addLast:
+ ((MessageNode new
+ receiver: rcvr
+ selector: (SelectorNode new key: #concatenateQuasiQuote code: nil)
+ arguments: args
+ precedence: 1)
+ notePrintingSelector: #printQuasiQuoteOn:indent:;
+ yourself).
+ ^true!

Item was changed:
  ----- Method: Decompiler>>send:super:numArgs: (in category 'instruction decoding') -----
  send: selector super: superFlag numArgs: numArgs
 
  | args rcvr selNode msgNode messages |
  args := Array new: numArgs.
  (numArgs to: 1 by: -1) do:
  [:i | args at: i put: stack removeLast].
  rcvr := stack removeLast.
  superFlag ifTrue: [rcvr := constructor codeSuper].
+ (self checkForMacroMessage: rcvr selector: selector arguments: args) ifFalse:
- ((#(blockCopy: closureCopy:copiedValues:) includes: selector)
-  and: [self checkForBlock: rcvr selector: selector arguments: args]) ifFalse:
  [selNode := constructor codeAnySelector: selector.
  rcvr == CascadeFlag
  ifTrue:
  ["May actually be a cascade or an ifNil: for value."
  self willJumpIfFalse
  ifTrue: "= generated by a case macro"
  [selector == #= ifTrue:
  [" = signals a case statement..."
  statements addLast: args first.
  stack addLast: rcvr. "restore CascadeFlag"
  ^ self].
  selector == #== ifTrue:
  [" == signals an ifNil: for value..."
  stack removeLast; removeLast.
  rcvr := stack removeLast.
  stack addLast: IfNilFlag;
  addLast: (constructor
  codeMessage: rcvr
  selector: selNode
  arguments: args).
  ^ self]]
  ifFalse:
  [(self willJumpIfTrue and: [selector == #==]) ifTrue:
  [" == signals an ifNotNil: for value..."
  stack removeLast; removeLast.
  rcvr := stack removeLast.
  stack addLast: IfNilFlag;
  addLast: (constructor
  codeMessage: rcvr
  selector: selNode
  arguments: args).
  ^ self]].
  msgNode := constructor
  codeCascadedMessage: selNode
  arguments: args.
  stack last == CascadeFlag ifFalse:
  ["Last message of a cascade"
  statements addLast: msgNode.
  messages := self popTo: stack removeLast.  "Depth saved by first dup"
  msgNode := constructor
  codeCascade: stack removeLast
  messages: messages]]
  ifFalse:
  [msgNode := constructor
  codeMessage: rcvr
  selector: selNode
  arguments: args].
  stack addLast: msgNode]!

Item was changed:
  ----- Method: MessageNode class>>initialize (in category 'class initialization') -----
  initialize
  "MessageNode initialize"
  MacroSelectors :=
  #( ifTrue: ifFalse: ifTrue:ifFalse: ifFalse:ifTrue:
  and: or:
  whileFalse: whileTrue: whileFalse whileTrue
  to:do: to:by:do:
  caseOf: caseOf:otherwise:
  ifNil: ifNotNil:  ifNil:ifNotNil: ifNotNil:ifNil:
+ repeat
+ nil "space for concatenateQuasiQuote" ).
- repeat ).
  MacroTransformers :=
  #( transformIfTrue: transformIfFalse: transformIfTrueIfFalse: transformIfFalseIfTrue:
  transformAnd: transformOr:
  transformWhile: transformWhile: transformWhile: transformWhile:
  transformToDo: transformToDo:
  transformCase: transformCase:
  transformIfNil: transformIfNil:  transformIfNilIfNotNil: transformIfNotNilIfNil:
+ transformRepeat:
+ nil "space for concatenateQuasiQuote" ).
- transformRepeat: ).
  MacroEmitters :=
  #( emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
  emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
  emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
  emitCodeForWhile:encoder:value: emitCodeForWhile:encoder:value:
  emitCodeForWhile:encoder:value: emitCodeForWhile:encoder:value:
  emitCodeForToDo:encoder:value: emitCodeForToDo:encoder:value:
  emitCodeForCase:encoder:value: emitCodeForCase:encoder:value:
  emitCodeForIfNil:encoder:value: emitCodeForIfNil:encoder:value:
  emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
+ emitCodeForRepeat:encoder:value:
+ nil "space for concatenateQuasiQuote").
- emitCodeForRepeat:encoder:value:).
  MacroSizers :=
  #( sizeCodeForIf:value: sizeCodeForIf:value: sizeCodeForIf:value: sizeCodeForIf:value:
  sizeCodeForIf:value: sizeCodeForIf:value:
  sizeCodeForWhile:value: sizeCodeForWhile:value: sizeCodeForWhile:value: sizeCodeForWhile:value:
  sizeCodeForToDo:value: sizeCodeForToDo:value:
  sizeCodeForCase:value: sizeCodeForCase:value:
  sizeCodeForIfNil:value: sizeCodeForIfNil:value: sizeCodeForIf:value: sizeCodeForIf:value:
+ sizeCodeForRepeat:value:
+ nil "space for concatenateQuasiQuote").
- sizeCodeForRepeat:value:).
  MacroPrinters :=
  #( printIfOn:indent: printIfOn:indent: printIfOn:indent: printIfOn:indent:
  printIfOn:indent: printIfOn:indent:
  printWhileOn:indent: printWhileOn:indent: printWhileOn:indent: printWhileOn:indent:
  printToDoOn:indent: printToDoOn:indent:
  printCaseOn:indent: printCaseOn:indent:
  printIfNil:indent: printIfNil:indent: printIfNilNotNil:indent: printIfNilNotNil:indent:
+ printRepeatOn:indent:
+ printQuasiQuoteOn:indent:)!
- printRepeatOn:indent:)!

Item was added:
+ ----- Method: MessageNode>>notePrintingSelector: (in category 'macro transformations') -----
+ notePrintingSelector: printingSelectorSymbol
+ "decompile"
+
+ special := MacroPrinters indexOf: printingSelectorSymbol!

Item was added:
+ ----- Method: MessageNode>>printQuasiQuoteOn:indent: (in category 'printing') -----
+ printQuasiQuoteOn: aStream indent: level
+ aStream nextPut: $`.
+ receiver elements do:
+ [:parseNode|
+ (parseNode isLiteralNode
+ and: [parseNode key class == 'literal' class])
+ ifTrue:
+ [parseNode key do:
+ [:char|
+ ('`[\' includes: char) ifTrue:
+ [aStream nextPut: $\].
+ aStream nextPut: char]]
+ ifFalse:
+ [(parseNode isMessageNode
+  and: [parseNode selector key == #value
+  and: [parseNode receiver isBlockNode]])
+ ifTrue:
+ [parseNode receiver printOn: aStream indent: 0]
+ ifFalse:
+ [aStream nextPut: $[.
+ parseNode printOn: aStream indent: 0.
+ aStream nextPut: $]]]].
+ aStream nextPut: $`!

Item was changed:
  ----- Method: Parser>>advance (in category 'scanning') -----
  advance
  | this |
  prevMark := hereMark.
  prevEnd := hereEnd.
  this := here.
  here := token.
  hereType := tokenType.
  hereMark := mark.
  hereEnd := source position - (aheadChar == DoItCharacter
  ifTrue: [hereChar == DoItCharacter
  ifTrue: [0]
  ifFalse: [1]]
  ifFalse: [2]).
+ hereType ~~ #backQuote ifTrue:
+ [self scanToken].
- self scanToken.
  "Transcript show: 'here: ', here printString, ' mark: ', hereMark printString, ' end: ', hereEnd printString; cr."
  ^this!

Item was changed:
  ----- Method: Parser>>expression (in category 'expression types') -----
  expression
 
+ (hereType == #word and: [tokenType == #leftArrow]) ifTrue:
+ [^self assignment: self variable].
+ hereType == #backQuote
+ ifTrue: [self quasiQuoteExpression]
+ ifFalse:
+ [hereType == #leftBrace
+ ifTrue: [self braceExpression]
+ ifFalse:
+ [self primaryExpression ifFalse:
+ [^false]]].
+ (self messagePart: 3 repeat: true) ifTrue:
+ [hereType == #semicolon ifTrue:
+ [self cascade]].
+ ^true!
- (hereType == #word and: [tokenType == #leftArrow])
- ifTrue: [^ self assignment: self variable].
- hereType == #leftBrace
- ifTrue: [self braceExpression]
- ifFalse: [self primaryExpression ifFalse: [^ false]].
- (self messagePart: 3 repeat: true)
- ifTrue: [hereType == #semicolon ifTrue: [self cascade]].
- ^ true!

Item was added:
+ ----- Method: Parser>>nonQuasiQuoteExpression (in category 'expression types') -----
+ nonQuasiQuoteExpression
+
+ (hereType == #word and: [tokenType == #leftArrow])
+ ifTrue: [^ self assignment: self variable].
+ hereType == #leftBrace
+ ifTrue: [self braceExpression]
+ ifFalse: [self primaryExpression ifFalse: [^ false]].
+ (self messagePart: 3 repeat: true)
+ ifTrue: [hereType == #semicolon ifTrue: [self cascade]].
+ ^ true!

Item was added:
+ ----- Method: Parser>>quasiQuoteExpression (in category 'expression types') -----
+ quasiQuoteExpression
+ "`quasi-quote`
+ => { elements } concatenateQuasiQuote
+ => MessageNode receiver: BraceNode selector: #concatenateQuasiQuote.
+
+ The syntax of quasi-quote is
+ quasi-quote := $` (characters | blockExpression) * $`
+ characters := (unescapedCharacter | $\ escapedCharacter) *
+
+ The semantics of quasi-quote are that each blockExpression is evaluated
+ left-to-right in the scope of the enclosing method or block.  The sequence
+ of interspersed character sequences and expressions are concatenated
+ left-to-right, sending asString to each element immediately prior to concatenation.
+ The concatenation is then the result of the expression.  It is always a new string.
+
+ The implementation inlines single-statement blocks into the brace expression that
+ comprises the receiver of concatenateQuasiQuote"
+
+ | elements locations stringStream loc |
+ elements := OrderedCollection new.
+ locations := OrderedCollection new.
+ stringStream := WriteStream on: (String new: 16).
+ [loc := hereMark + requestorOffset.
+ hereType == #doit ifTrue:
+ [^self expected: 'back quote'].
+ hereType == #leftBracket
+ ifTrue:
+ [self scanToken; advance.
+ parseNode := nil.
+ self blockExpression.
+ parseNode statements size = 1
+ ifTrue:
+ [elements addLast: parseNode statements first]
+ ifFalse:
+ [elements addLast: (MessageNode new
+ receiver: parseNode
+ selector: #value
+ arguments: #()
+ precedence: 1
+ from: encoder)].
+ source position: hereMark - 1.
+ [source peek ~~ $]] whileTrue:
+ [source position: source position - 1].
+ source next.
+ self step; step.
+ self setHereTypeForQuasiQuote.
+ locations addLast: loc]
+ ifFalse:
+ [(self scanQuasiQuoteCharactersUsing: stringStream) ifNotNil:
+ [:lit|
+ elements addLast: lit.
+ locations addLast: loc]].
+ hereType ~~ #backQuote] whileTrue.
+ parseNode := MessageNode new
+ receiver: (BraceNode new elements: elements sourceLocations: locations)
+ selector: #concatenateQuasiQuote
+ arguments: #()
+ precedence: 1
+ from: encoder.
+ self scanToken; advance.
+ ^true!

Item was changed:
+ ----- Method: Parser>>queriedUnusedTemporaries (in category 'temps') -----
- ----- Method: Parser>>queriedUnusedTemporaries (in category 'accessing') -----
  queriedUnusedTemporaries
 
  queriedUnusedTemporaries ifNil:
  [queriedUnusedTemporaries := Dictionary new].
  ^queriedUnusedTemporaries!

Item was added:
+ ----- Method: Parser>>scanQuasiQuoteCharactersUsing: (in category 'scanning') -----
+ scanQuasiQuoteCharactersUsing: stringStream
+ "Answer the next non-empty sequence of characters in a quasi-quote string, or nil, if none."
+ stringStream reset.
+ [hereChar ~~ $` and: [hereChar ~~ $[ and: [hereChar ~~ DoItCharacter]]] whileTrue:
+ [hereChar == $\
+ ifTrue:
+ [stringStream nextPut: aheadChar. self step]
+ ifFalse:
+ [stringStream nextPut: hereChar].
+ self step].
+ self setHereTypeForQuasiQuote.
+ ^stringStream position > 0 ifTrue:
+ [encoder encodeLiteral: stringStream contents]!

Item was added:
+ ----- Method: Parser>>setHereTypeForQuasiQuote (in category 'scanning') -----
+ setHereTypeForQuasiQuote
+ "Set hereType appropriately based on hereChar.  Used only for quasi-quote parsing."
+ hereChar == $`
+ ifTrue:
+ [hereType := #backQuote.
+ self step]
+ ifFalse:
+ [hereChar == $[
+ ifTrue:
+ [hereType := #leftBracket.
+ self step]
+ ifFalse:
+ [hereChar == DoItCharacter ifTrue:
+ [hereType := #doit]]]!

Item was changed:
+ ----- Method: Parser>>tempsMark (in category 'temps') -----
- ----- Method: Parser>>tempsMark (in category 'accessing') -----
  tempsMark
  ^ tempsMark!

Item was changed:
+ ----- Method: Parser>>tempsMark: (in category 'temps') -----
- ----- Method: Parser>>tempsMark: (in category 'accessing') -----
  tempsMark: aNumber
  tempsMark := aNumber!

Item was changed:
  ----- Method: Scanner class>>initializeTypeTable (in category 'initialization') -----
  initializeTypeTable
  "self initializeTypeTable"
 
  | newTable |
  newTable := Array new: 256 withAll: #xBinary. "default"
  newTable atAll: #(9 10 12 13 32 ) put: #xDelimiter. "tab lf ff cr space"
  newTable atAll: ($0 asciiValue to: $9 asciiValue) put: #xDigit.
 
  1 to: 255
  do: [:index |
  (Character value: index) isLetter
  ifTrue: [newTable at: index put: #xLetter]].
 
  newTable at: $" asciiValue put: #xDoubleQuote.
  newTable at: $# asciiValue put: #xLitQuote.
  newTable at: $$ asciiValue put: #xDollar.
  newTable at: $' asciiValue put: #xSingleQuote.
+ newTable at: $` asciiValue put: #backQuote.
  newTable at: $: asciiValue put: #xColon.
  newTable at: $( asciiValue put: #leftParenthesis.
  newTable at: $) asciiValue put: #rightParenthesis.
  newTable at: $. asciiValue put: #period.
  newTable at: $; asciiValue put: #semicolon.
  newTable at: $[ asciiValue put: #leftBracket.
  newTable at: $] asciiValue put: #rightBracket.
  newTable at: ${ asciiValue put: #leftBrace.
  newTable at: $} asciiValue put: #rightBrace.
  newTable at: $^ asciiValue put: #upArrow.
  newTable at: $_ asciiValue put: #xUnderscore.
  newTable at: $| asciiValue put: #verticalBar.
  TypeTable := newTable "bon voyage!!"!

Hi All,

--
best,

I'm reminded at this point of SmalltalkAgents which used curly quotes (single and double) so that literals and comments could nest. FWIW

Hi All,

    I had fun implementing a quasi-quote for Squeak today.  This is a convenient way of embedding substrings in format strings (a little like printf), and, because it uses a different quote character, a convenient way of embedding code form other languages in a string literal.

An example of the former usage is

    `hello [#cruel] world`

which evaluates to

    'hello cruel world'

And

    `Float pi is [Float pi]`

evaluates to

    'Float pi is 3.141592653589793'

An example of the latter use is that one can write

    `printf("%s: %c\\n", "a string", 'C');`

instead of

    'printf("%s: %c\n", "a string", ''C'');'

This last example shows a limitation; The use of \ to escape characters ($\ $[ and $`) in quasi-quote might not be such a good choice.

Anyway I thought I'd put this in the in-box for people to play with and savage.  Please let me know what you think, both about the semantics and the implementation.  This is a quick hack and I'm sure that there's plenty of scope for clean-up.

cheers

Eliot

On Tue, Feb 5, 2013 at 9:54 PM, <[hidden email]> wrote:

A new version of Compiler was added to project The Inbox:
http://source.squeak.org/inbox/Compiler.quasiquote-eem.248.mcz

==================== Summary ====================

Name: Compiler.quasiquote-eem.248
Author: eem
Time: 5 February 2013, 9:54:20.317 pm
UUID: ef044906-3339-48cc-856b-9b5172e3e81b
Ancestors: Compiler-cwp.247

Add a quasi-quote form that allows convenient embedding
of substrings within a format string, and provides a
convenient way of embedding literal strings within an
alternative literal string whose string delimiter is different.

e.g.
        `hello [#cruel] world!`
evaluates to
        'hello cruel world'.

        `S1[B1]...SN[BN]SN+1`

is equivalent to
        { 'S1'. [B1] value. ... 'SN'. [BN] value. 'SN+1' } concatenateQuasiQuote
where concatenateQuasiQuote sends asString to each
element and answers the concatenation of those elements.

however, single-statement blocks are inlined, so e.g. the
above `hello [#cruel] world!` is compiled as
        { 'hello '. #cruel. ' world!' } concatenateQuasiQuote

See Tests.quasiquote-eem.188 for tests and examples.

=============== Diff against Compiler-cwp.247 ===============

Item was added:
+ ----- Method: Array>>concatenateQuasiQuote (in category '*Compiler-support') -----
+ concatenateQuasiQuote
+       "This method is used in compilation of quasi-quote constructs.
+       It MUST NOT be deleted or altered."
+
+       | s sz |
+       sz := self size.
+       s := WriteStream on: (String new: sz * 16).
+       1 to: sz do:
+               [:i| s nextPutAll: (self at: i) asString].
+       ^s contents!

Item was removed:
- ----- Method: Decompiler>>checkForBlock:selector:arguments: (in category 'control') -----
- checkForBlock: receiver selector: selector arguments: arguments
-       selector == #blockCopy: ifTrue:
-               [^self checkForBlockCopy: receiver].
-       self assert: selector == #closureCopy:copiedValues:.
-       ^self checkForClosureCopy: receiver arguments: arguments!

Item was added:
+ ----- Method: Decompiler>>checkForMacroMessage:selector:arguments: (in category 'control') -----
+ checkForMacroMessage: rcvr selector: selector arguments: args
+       ^       (selector == #concatenateQuasiQuote
+                  and: [self checkForQuasiQuote: rcvr selector: selector arguments: args])
+         or: [(#closureCopy:copiedValues: == selector
+                  and: [self checkForClosureCopy: rcvr arguments: args])
+         or: [#blockCopy: == selector
+                 and: [self checkForBlockCopy: rcvr]]]!

Item was added:
+ ----- Method: Decompiler>>checkForQuasiQuote:selector:arguments: (in category 'control') -----
+ checkForQuasiQuote: rcvr "<BraceNode>" selector: selector "<Symbol>" arguments: args "<Array>"
+       stack addLast:
+               ((MessageNode new
+                               receiver: rcvr
+                               selector: (SelectorNode new key: #concatenateQuasiQuote code: nil)
+                               arguments: args
+                               precedence: 1)
+                       notePrintingSelector: #printQuasiQuoteOn:indent:;
+                       yourself).
+       ^true!

Item was changed:
  ----- Method: Decompiler>>send:super:numArgs: (in category 'instruction decoding') -----
  send: selector super: superFlag numArgs: numArgs

        | args rcvr selNode msgNode messages |
        args := Array new: numArgs.
        (numArgs to: 1 by: -1) do:
                [:i | args at: i put: stack removeLast].
        rcvr := stack removeLast.
        superFlag ifTrue: [rcvr := constructor codeSuper].
+       (self checkForMacroMessage: rcvr selector: selector arguments: args) ifFalse:
-       ((#(blockCopy: closureCopy:copiedValues:) includes: selector)
-         and: [self checkForBlock: rcvr selector: selector arguments: args]) ifFalse:
                [selNode := constructor codeAnySelector: selector.
                rcvr == CascadeFlag
                        ifTrue:
                                ["May actually be a cascade or an ifNil: for value."
                                self willJumpIfFalse
                                        ifTrue: "= generated by a case macro"
                                                [selector == #= ifTrue:
                                                        [" = signals a case statement..."
                                                        statements addLast: args first.
                                                        stack addLast: rcvr. "restore CascadeFlag"
                                                        ^ self].
                                                selector == #== ifTrue:
                                                        [" == signals an ifNil: for value..."
                                                        stack removeLast; removeLast.
                                                        rcvr := stack removeLast.
                                                        stack addLast: IfNilFlag;
                                                                addLast: (constructor
                                                                        codeMessage: rcvr
                                                                        selector: selNode
                                                                        arguments: args).
                                                        ^ self]]
                                        ifFalse:
                                                [(self willJumpIfTrue and: [selector == #==]) ifTrue:
                                                        [" == signals an ifNotNil: for value..."
                                                        stack removeLast; removeLast.
                                                        rcvr := stack removeLast.
                                                        stack addLast: IfNilFlag;
                                                                addLast: (constructor
                                                                        codeMessage: rcvr
                                                                        selector: selNode
                                                                        arguments: args).
                                                        ^ self]].
                                msgNode := constructor
                                                                codeCascadedMessage: selNode
                                                                arguments: args.
                                stack last == CascadeFlag ifFalse:
                                        ["Last message of a cascade"
                                        statements addLast: msgNode.
                                        messages := self popTo: stack removeLast.  "Depth saved by first dup"
                                        msgNode := constructor
                                                                        codeCascade: stack removeLast
                                                                        messages: messages]]
                        ifFalse:
                                [msgNode := constructor
                                                        codeMessage: rcvr
                                                        selector: selNode
                                                        arguments: args].
                stack addLast: msgNode]!

Item was changed:
  ----- Method: MessageNode class>>initialize (in category 'class initialization') -----
  initialize
        "MessageNode initialize"
        MacroSelectors :=
                #(      ifTrue: ifFalse: ifTrue:ifFalse: ifFalse:ifTrue:
                        and: or:
                        whileFalse: whileTrue: whileFalse whileTrue
                        to:do: to:by:do:
                        caseOf: caseOf:otherwise:
                        ifNil: ifNotNil:  ifNil:ifNotNil: ifNotNil:ifNil:
+                       repeat
+                       nil "space for concatenateQuasiQuote" ).
-                       repeat ).
        MacroTransformers :=
                #(      transformIfTrue: transformIfFalse: transformIfTrueIfFalse: transformIfFalseIfTrue:
                        transformAnd: transformOr:
                        transformWhile: transformWhile: transformWhile: transformWhile:
                        transformToDo: transformToDo:
                        transformCase: transformCase:
                        transformIfNil: transformIfNil:  transformIfNilIfNotNil: transformIfNotNilIfNil:
+                       transformRepeat:
+                       nil "space for concatenateQuasiQuote" ).
-                       transformRepeat: ).
        MacroEmitters :=
                #(      emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
                        emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
                        emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
                        emitCodeForWhile:encoder:value: emitCodeForWhile:encoder:value:
                        emitCodeForWhile:encoder:value: emitCodeForWhile:encoder:value:
                        emitCodeForToDo:encoder:value: emitCodeForToDo:encoder:value:
                        emitCodeForCase:encoder:value: emitCodeForCase:encoder:value:
                        emitCodeForIfNil:encoder:value: emitCodeForIfNil:encoder:value:
                        emitCodeForIf:encoder:value: emitCodeForIf:encoder:value:
+                       emitCodeForRepeat:encoder:value:
+                       nil "space for concatenateQuasiQuote").
-                       emitCodeForRepeat:encoder:value:).
        MacroSizers :=
                #(      sizeCodeForIf:value: sizeCodeForIf:value: sizeCodeForIf:value: sizeCodeForIf:value:
                        sizeCodeForIf:value: sizeCodeForIf:value:
                        sizeCodeForWhile:value: sizeCodeForWhile:value: sizeCodeForWhile:value: sizeCodeForWhile:value:
                        sizeCodeForToDo:value: sizeCodeForToDo:value:
                        sizeCodeForCase:value: sizeCodeForCase:value:
                        sizeCodeForIfNil:value: sizeCodeForIfNil:value: sizeCodeForIf:value: sizeCodeForIf:value:
+                       sizeCodeForRepeat:value:
+                       nil "space for concatenateQuasiQuote").
-                       sizeCodeForRepeat:value:).
        MacroPrinters :=
                #(      printIfOn:indent: printIfOn:indent: printIfOn:indent: printIfOn:indent:
                        printIfOn:indent: printIfOn:indent:
                        printWhileOn:indent: printWhileOn:indent: printWhileOn:indent: printWhileOn:indent:
                        printToDoOn:indent: printToDoOn:indent:
                        printCaseOn:indent: printCaseOn:indent:
                        printIfNil:indent: printIfNil:indent: printIfNilNotNil:indent: printIfNilNotNil:indent:
+                       printRepeatOn:indent:
+                       printQuasiQuoteOn:indent:)!
-                       printRepeatOn:indent:)!

Item was added:
+ ----- Method: MessageNode>>notePrintingSelector: (in category 'macro transformations') -----
+ notePrintingSelector: printingSelectorSymbol
+       "decompile"
+
+       special := MacroPrinters indexOf: printingSelectorSymbol!

Item was added:
+ ----- Method: MessageNode>>printQuasiQuoteOn:indent: (in category 'printing') -----
+ printQuasiQuoteOn: aStream indent: level
+       aStream nextPut: $`.
+       receiver elements do:
+               [:parseNode|
+               (parseNode isLiteralNode
+                and: [parseNode key class == 'literal' class])
+                       ifTrue:
+                               [parseNode key do:
+                                       [:char|
+                                       ('`[\' includes: char) ifTrue:
+                                               [aStream nextPut: $\].
+                                       aStream nextPut: char]]
+                       ifFalse:
+                               [(parseNode isMessageNode
+                                 and: [parseNode selector key == #value
+                                 and: [parseNode receiver isBlockNode]])
+                                       ifTrue:
+                                               [parseNode receiver printOn: aStream indent: 0]
+                                       ifFalse:
+                                               [aStream nextPut: $[.
+                                                parseNode printOn: aStream indent: 0.
+                                                aStream nextPut: $]]]].
+       aStream nextPut: $`!

Item was changed:
  ----- Method: Parser>>advance (in category 'scanning') -----
  advance
        | this |
        prevMark := hereMark.
        prevEnd := hereEnd.
        this := here.
        here := token.
        hereType := tokenType.
        hereMark := mark.
        hereEnd := source position - (aheadChar == DoItCharacter
                ifTrue: [hereChar == DoItCharacter
                        ifTrue: [0]
                        ifFalse: [1]]
                ifFalse: [2]).
+       hereType ~~ #backQuote ifTrue:
+               [self scanToken].
-       self scanToken.
        "Transcript show: 'here: ', here printString, ' mark: ', hereMark printString, ' end: ', hereEnd printString; cr."
        ^this!

Item was changed:
  ----- Method: Parser>>expression (in category 'expression types') -----
  expression

+       (hereType == #word and: [tokenType == #leftArrow]) ifTrue:
+               [^self assignment: self variable].
+       hereType == #backQuote
+               ifTrue: [self quasiQuoteExpression]
+               ifFalse:
+                       [hereType == #leftBrace
+                               ifTrue: [self braceExpression]
+                               ifFalse:
+                                       [self primaryExpression ifFalse:
+                                               [^false]]].
+       (self messagePart: 3 repeat: true) ifTrue:
+               [hereType == #semicolon ifTrue:
+                       [self cascade]].
+       ^true!
-       (hereType == #word and: [tokenType == #leftArrow])
-               ifTrue: [^ self assignment: self variable].
-       hereType == #leftBrace
-               ifTrue: [self braceExpression]
-               ifFalse: [self primaryExpression ifFalse: [^ false]].
-       (self messagePart: 3 repeat: true)
-               ifTrue: [hereType == #semicolon ifTrue: [self cascade]].
-       ^ true!

Item was added:
+ ----- Method: Parser>>nonQuasiQuoteExpression (in category 'expression types') -----
+ nonQuasiQuoteExpression
+
+       (hereType == #word and: [tokenType == #leftArrow])
+               ifTrue: [^ self assignment: self variable].
+       hereType == #leftBrace
+               ifTrue: [self braceExpression]
+               ifFalse: [self primaryExpression ifFalse: [^ false]].
+       (self messagePart: 3 repeat: true)
+               ifTrue: [hereType == #semicolon ifTrue: [self cascade]].
+       ^ true!

Item was added:
+ ----- Method: Parser>>quasiQuoteExpression (in category 'expression types') -----
+ quasiQuoteExpression
+       "`quasi-quote`
+               => { elements } concatenateQuasiQuote
+                       => MessageNode receiver: BraceNode selector: #concatenateQuasiQuote.
+
+        The syntax of quasi-quote is
+               quasi-quote := $` (characters | blockExpression) * $`
+               characters := (unescapedCharacter | $\ escapedCharacter) *
+
+       The semantics of quasi-quote are that each blockExpression is evaluated
+        left-to-right in the scope of the enclosing method or block.  The sequence
+        of interspersed character sequences and expressions are concatenated
+        left-to-right, sending asString to each element immediately prior to concatenation.
+        The concatenation is then the result of the expression.  It is always a new string.
+
+        The implementation inlines single-statement blocks into the brace expression that
+        comprises the receiver of concatenateQuasiQuote"
+
+       | elements locations stringStream loc |
+       elements := OrderedCollection new.
+       locations := OrderedCollection new.
+       stringStream := WriteStream on: (String new: 16).
+       [loc := hereMark + requestorOffset.
+        hereType == #doit ifTrue:
+               [^self expected: 'back quote'].
+        hereType == #leftBracket
+               ifTrue:
+                       [self scanToken; advance.
+                        parseNode := nil.
+                        self blockExpression.
+                        parseNode statements size = 1
+                               ifTrue:
+                                       [elements addLast: parseNode statements first]
+                               ifFalse:
+                                       [elements addLast: (MessageNode new
+                                                                                       receiver: parseNode
+                                                                                       selector: #value
+                                                                                       arguments: #()
+                                                                                       precedence: 1
+                                                                                       from: encoder)].
+                        source position: hereMark - 1.
+                        [source peek ~~ $]] whileTrue:
+                               [source position: source position - 1].
+                        source next.
+                        self step; step.
+                        self setHereTypeForQuasiQuote.
+                        locations addLast: loc]
+               ifFalse:
+                       [(self scanQuasiQuoteCharactersUsing: stringStream) ifNotNil:
+                               [:lit|
+                                elements addLast: lit.
+                                locations addLast: loc]].
+        hereType ~~ #backQuote] whileTrue.
+       parseNode := MessageNode new
+                                       receiver: (BraceNode new elements: elements sourceLocations: locations)
+                                       selector: #concatenateQuasiQuote
+                                       arguments: #()
+                                       precedence: 1
+                                       from: encoder.
+       self scanToken; advance.
+       ^true!

Item was changed:
+ ----- Method: Parser>>queriedUnusedTemporaries (in category 'temps') -----
- ----- Method: Parser>>queriedUnusedTemporaries (in category 'accessing') -----
  queriedUnusedTemporaries

        queriedUnusedTemporaries ifNil:
                [queriedUnusedTemporaries := Dictionary new].
        ^queriedUnusedTemporaries!

Item was added:
+ ----- Method: Parser>>scanQuasiQuoteCharactersUsing: (in category 'scanning') -----
+ scanQuasiQuoteCharactersUsing: stringStream
+       "Answer the next non-empty sequence of characters in a quasi-quote string, or nil, if none."
+       stringStream reset.
+       [hereChar ~~ $` and: [hereChar ~~ $[ and: [hereChar ~~ DoItCharacter]]] whileTrue:
+               [hereChar == $\
+                       ifTrue:
+                               [stringStream nextPut: aheadChar. self step]
+                       ifFalse:
+                               [stringStream nextPut: hereChar].
+                self step].
+       self setHereTypeForQuasiQuote.
+       ^stringStream position > 0 ifTrue:
+               [encoder encodeLiteral: stringStream contents]!

Item was added:
+ ----- Method: Parser>>setHereTypeForQuasiQuote (in category 'scanning') -----
+ setHereTypeForQuasiQuote
+       "Set hereType appropriately based on hereChar.  Used only for quasi-quote parsing."
+       hereChar == $`
+               ifTrue:
+                       [hereType := #backQuote.
+                        self step]
+               ifFalse:
+                       [hereChar == $[
+                               ifTrue:
+                                       [hereType := #leftBracket.
+                                        self step]
+                               ifFalse:
+                                       [hereChar == DoItCharacter ifTrue:
+                                               [hereType := #doit]]]!

Item was changed:
+ ----- Method: Parser>>tempsMark (in category 'temps') -----
- ----- Method: Parser>>tempsMark (in category 'accessing') -----
  tempsMark
        ^ tempsMark!

Item was changed:
+ ----- Method: Parser>>tempsMark: (in category 'temps') -----
- ----- Method: Parser>>tempsMark: (in category 'accessing') -----
  tempsMark: aNumber
  tempsMark := aNumber!

Item was changed:
  ----- Method: Scanner class>>initializeTypeTable (in category 'initialization') -----
  initializeTypeTable
        "self initializeTypeTable"

        | newTable |
        newTable := Array new: 256 withAll: #xBinary. "default"
        newTable atAll: #(9 10 12 13 32 ) put: #xDelimiter. "tab lf ff cr space"
        newTable atAll: ($0 asciiValue to: $9 asciiValue) put: #xDigit.

        1 to: 255
                do: [:index |
                        (Character value: index) isLetter
                                ifTrue: [newTable at: index put: #xLetter]].

        newTable at: $" asciiValue put: #xDoubleQuote.
        newTable at: $# asciiValue put: #xLitQuote.
        newTable at: $$ asciiValue put: #xDollar.
        newTable at: $' asciiValue put: #xSingleQuote.
+       newTable at: $` asciiValue put: #backQuote.
        newTable at: $: asciiValue put: #xColon.
        newTable at: $( asciiValue put: #leftParenthesis.
        newTable at: $) asciiValue put: #rightParenthesis.
        newTable at: $. asciiValue put: #period.
        newTable at: $; asciiValue put: #semicolon.
        newTable at: $[ asciiValue put: #leftBracket.
        newTable at: $] asciiValue put: #rightBracket.
        newTable at: ${ asciiValue put: #leftBrace.
        newTable at: $} asciiValue put: #rightBrace.
        newTable at: $^ asciiValue put: #upArrow.
        newTable at: $_ asciiValue put: #xUnderscore.
        newTable at: $| asciiValue put: #verticalBar.
        TypeTable := newTable "bon voyage!!"!

--
best,

Eliot