welcome: please sign in

Diff for "DomTool/LanguageReference"

Differences between revisions 2 and 131 (spanning 129 versions)
Revision 2 as of 2006-12-17 16:59:10
Size: 2879
Editor: AdamChlipala
Comment: Types
Revision 131 as of 2008-03-23 16:33:35
Size: 2105
Editor: 212
Comment: . - http://ghe8ghwelgh.cn/celebritypiercing.html celebrity piercing - http://ghe8ghwelgh.cn/cryptographyhistory.html cryptography history - http://ghe8ghwelgh.cn/stalagmite.html stalagmite - http://gh
Deletions are marked like this. Additions are marked like this.
Line 1: Line 1:
This page gives an in-depth specification of the DomTool language. Most members would probably prefer the more informal presentation in DomTool/UserGuide.

[[TableOfContents()]]

= Source code =

For a complete, precise, and accurate grammatical specification, see the lexer and parser specifications `src/domtool.lex` and `src/domtool.grm` in the DomTool source code. See `src/tycheck.sml` for the type-checker implementation. ["DomTool/Building"] has information on obtaining the source.

= Token conventions =

In the grammars that follow, we use these lexical token class names:

|| '''Name''' || '''Description''' ||
|| `Symbol` || Identifier starting with a lowercase letter ||
|| `CSymbol` || Identifier starting with a capital letter ||

= Predicates =

DomTool uses '''predicates''' to describe in what contexts an action may occur. For instance, web-related actions should only occur inside the scope of a virtual host directive. Predicates are built up following the grammar in the table below, using the letter `P` as the non-terminal for predicates.

Meanings are given as statements that must hold about the context where an action is found. The context is represented as a stack of '''context IDs''' which have been declared with `context` declarations.

|| '''Syntax''' || '''Description''' || '''Meaning''' ||
|| `Root` || Root || The stack is empty. ||
|| `CSymbol` || Context ID || `CSymbol` is on the top of the stack. ||
|| `^P` || Suffixes || Some (not necessarily strict) suffix of the stack matches `P`. ||
|| `!P` || Not || The stack ''doesn't'' match `P`. ||
|| `P1 & P2` || And || The stack matches both `P1` and `P2`. ||
|| `(P)` || Grouping || Identical to `P` ||

= Types =

Types describe expressions. As is standard in statically-typed programming languages, they are used only for validation purposes and have no real effect on the "output" of a program. The following table gives the grammar of types `T`. The section on expressions will give the meanings of types in terms of which expressions have which types.

|| '''Syntax''' || '''Description''' ||
|| `Symbol` || Extern type ||
|| `[T]` || List of `T`s ||
|| `T1 -> T2` || Function from `T1` to `T2` ||
|| `[P]` || Action allowed only when `P` is satisified; requires no environment variables on input and writes none of its own ||
|| `[P] {CSymbol1 : T1, ..., CSymbolN : TN}` || Action that requires environment variables `CSymbol1`, ..., `CSymbolN` to have the given types when run ||
|| `[P] {CSymbol1_1 : T1_1, ..., CSymbol1_N : T1_N} => {CSymbol2_1 : T2_1, ..., CSymbol2_M : T2_M}` || Like the last case, but the second set of typed environment variables describes what the action will write ||
|| `P => T` || A nested action that requires that its nested configuration satisfy `P`; `T` should be some action type ||
|| `(T)` || Grouping ||
. - http://ghe8ghwelgh.cn/celebritypiercing.html celebrity piercing - http://ghe8ghwelgh.cn/cryptographyhistory.html cryptography history - http://ghe8ghwelgh.cn/stalagmite.html stalagmite - http://ghe8ghwelgh.cn/kiterunnerchaptersummaries.html kite runner chapter summaries - http://ghe8ghwelgh.cn/drugrehabcentersinflorida.html drug rehab centers in florida - http://ghe8ghwelgh.cn/hangingtree.html hanging tree - http://ghe8ghwelgh.cn/tahoeluxuryproperties.html tahoe luxury properties - http://ghe8ghwelgh.cn/derekzoolander.html derek zoolander - http://ghe8ghwelgh.cn/usbaudiointerface.html usb audio interface - http://ghe8ghwelgh.cn/windmillcycles.html windmill cycles - http://ghe8ghwelgh.cn/tinctureofbenzoin.html tincture of benzoin - http://ghe8ghwelgh.cn/milspecs.html mil specs - http://ghe8ghwelgh.cn/usembassykingston.html us embassy kingston - http://ghe8ghwelgh.cn/tropicalpaintings.html tropical paintings - http://ghe8ghwelgh.cn/mangaschoolgirls.html manga school girls - http://ghe8ghwelgh.cn/ps2discreaderror.html ps2 disc read error - http://ghe8ghwelgh.cn/chainsprockets.html chain sprockets - http://ghe8ghwelgh.cn/mswprograms.html msw programs - http://ghe8ghwelgh.cn/acryinthewild.html a cry in the wild - http://ghe8ghwelgh.cn/tirepressuremonitoringsystem.html tire pressure monitoring system - http://ghe8ghwelgh.cn/businessmodeling.html business modeling - http://ghe8ghwelgh.cn/engineblowers.html engine blowers - http://ghe8ghwelgh.cn/microscale.html microscale - http://ghe8ghwelgh.cn/dailysciencenews.html daily science news - http://ghe8ghwelgh.cn/homesforsalemesaaz.html homes for sale mesa az - http://ghe8ghwelgh.cn/summerandsmoke.html summer and smoke - http://ghe8ghwelgh.cn/mizuage.html mizuage - http://ghe8ghwelgh.cn/f650gs.html f650gs - http://ghe8ghwelgh.cn/microsoftspidersolitaire.html microsoft spider solitaire - http://ghe8ghwelgh.cn/toddlerraincoats.html toddler raincoats - http://ghe8ghwelgh.cn/odysseusjourney.html odysseus journey - http://ghe8ghwelgh.cn/juniorolympicsvolleyball.html junior olympics volleyball -
----
CategorySystemAdministration

. - http://ghe8ghwelgh.cn/celebritypiercing.html celebrity piercing - http://ghe8ghwelgh.cn/cryptographyhistory.html cryptography history - http://ghe8ghwelgh.cn/stalagmite.html stalagmite - http://ghe8ghwelgh.cn/kiterunnerchaptersummaries.html kite runner chapter summaries - http://ghe8ghwelgh.cn/drugrehabcentersinflorida.html drug rehab centers in florida - http://ghe8ghwelgh.cn/hangingtree.html hanging tree - http://ghe8ghwelgh.cn/tahoeluxuryproperties.html tahoe luxury properties - http://ghe8ghwelgh.cn/derekzoolander.html derek zoolander - http://ghe8ghwelgh.cn/usbaudiointerface.html usb audio interface - http://ghe8ghwelgh.cn/windmillcycles.html windmill cycles - http://ghe8ghwelgh.cn/tinctureofbenzoin.html tincture of benzoin - http://ghe8ghwelgh.cn/milspecs.html mil specs - http://ghe8ghwelgh.cn/usembassykingston.html us embassy kingston - http://ghe8ghwelgh.cn/tropicalpaintings.html tropical paintings - http://ghe8ghwelgh.cn/mangaschoolgirls.html manga school girls - http://ghe8ghwelgh.cn/ps2discreaderror.html ps2 disc read error - http://ghe8ghwelgh.cn/chainsprockets.html chain sprockets - http://ghe8ghwelgh.cn/mswprograms.html msw programs - http://ghe8ghwelgh.cn/acryinthewild.html a cry in the wild - http://ghe8ghwelgh.cn/tirepressuremonitoringsystem.html tire pressure monitoring system - http://ghe8ghwelgh.cn/businessmodeling.html business modeling - http://ghe8ghwelgh.cn/engineblowers.html engine blowers - http://ghe8ghwelgh.cn/microscale.html microscale - http://ghe8ghwelgh.cn/dailysciencenews.html daily science news - http://ghe8ghwelgh.cn/homesforsalemesaaz.html homes for sale mesa az - http://ghe8ghwelgh.cn/summerandsmoke.html summer and smoke - http://ghe8ghwelgh.cn/mizuage.html mizuage - http://ghe8ghwelgh.cn/f650gs.html f650gs - http://ghe8ghwelgh.cn/microsoftspidersolitaire.html microsoft spider solitaire - http://ghe8ghwelgh.cn/toddlerraincoats.html toddler raincoats - http://ghe8ghwelgh.cn/odysseusjourney.html odysseus journey - http://ghe8ghwelgh.cn/juniorolympicsvolleyball.html junior olympics volleyball -


CategorySystemAdministration

DomTool/LanguageReference (last edited 2010-01-27 11:43:02 by AdamChlipala)