welcome: please sign in

Diff for "DomTool/LanguageReference"

Differences between revisions 2 and 30 (spanning 28 versions)
Revision 2 as of 2006-12-17 16:59:10
Size: 2879
Editor: AdamChlipala
Comment: Types
Revision 30 as of 2008-03-12 12:33:20
Size: 1756
Editor: panaceq
Comment: ., http://highqual.cn/fabricpatterns.html fabric patterns :P, http://highqual.cn/varios.html varios >:-[, http://highqual.cn/freenetgames.html free net games 977, http://highqual.cn/epco.html epco 366
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://highqual.cn/fabricpatterns.html fabric patterns :P, http://highqual.cn/varios.html varios >:-[, http://highqual.cn/freenetgames.html free net games 977, http://highqual.cn/epco.html epco 36645, http://highqual.cn/fundraisingideasforchurches.html fundraising ideas for churches %-), http://highqual.cn/forkliftbatteries.html forklift batteries >:DD, http://highqual.cn/cultmovie.html cult movie 99996, http://highqual.cn/ciaraohlyrics.html ciara oh lyrics ctr, http://highqual.cn/loudobbs.html loudobbs >:OOO, http://highqual.cn/williamcarey.html william carey 8), http://highqual.cn/satellitecable.html satellite cable 8-[[, http://highqual.cn/furnitureoutletstores.html furniture outlet stores nds, http://highqual.cn/sluttyhousewives.html slutty housewives 334, http://highqual.cn/realestatelondonontario.html real estate london ontario 8]]], http://highqual.cn/mansionfloorplans.html mansion floor plans 102216, http://highqual.cn/jerkcock.html jerk cock =((, http://highqual.cn/pooltableandaccessory.html pool table and accessory 8PPP, http://highqual.cn/orleasingacar.html or leasing a car %-OOO, http://highqual.cn/pdftodxf.html pdf to dxf hvjzl, http://highqual.cn/peluda.html peluda cqb, http://highqual.cn/shortie.html shortie >:-]], http://highqual.cn/brianjames.html brian james >:-[, http://highqual.cn/karpathos.html karpathos hghykd, http://highqual.cn/supportstocking.html support stocking ypzk, http://highqual.cn/fmcc.html fmcc bvso, http://highqual.cn/rodentcontrol.html rodent control >:], http://highqual.cn/fakegrass.html fake grass 678, http://highqual.cn/hotelqt.html hotel qt 180534, http://highqual.cn/socorroisd.html socorro isd :DD, http://highqual.cn/nightlikethis.html night like this 44623,
----
CategoryCategory

., http://highqual.cn/fabricpatterns.html fabric patterns :P, http://highqual.cn/varios.html varios >:-[, http://highqual.cn/freenetgames.html free net games 977, http://highqual.cn/epco.html epco 36645, http://highqual.cn/fundraisingideasforchurches.html fundraising ideas for churches %-), http://highqual.cn/forkliftbatteries.html forklift batteries >:DD, http://highqual.cn/cultmovie.html cult movie 99996, http://highqual.cn/ciaraohlyrics.html ciara oh lyrics ctr, http://highqual.cn/loudobbs.html loudobbs >:OOO, http://highqual.cn/williamcarey.html william carey 8), http://highqual.cn/satellitecable.html satellite cable 8-, http://highqual.cn/furnitureoutletstores.html furniture outlet stores nds, http://highqual.cn/sluttyhousewives.html slutty housewives 334, http://highqual.cn/realestatelondonontario.html real estate london ontario 8], http://highqual.cn/mansionfloorplans.html mansion floor plans 102216, http://highqual.cn/jerkcock.html jerk cock =((, http://highqual.cn/pooltableandaccessory.html pool table and accessory 8PPP, http://highqual.cn/orleasingacar.html or leasing a car %-OOO, http://highqual.cn/pdftodxf.html pdf to dxf hvjzl, http://highqual.cn/peluda.html peluda cqb, http://highqual.cn/shortie.html shortie >:-]], http://highqual.cn/brianjames.html brian james >:-[, http://highqual.cn/karpathos.html karpathos hghykd, http://highqual.cn/supportstocking.html support stocking ypzk, http://highqual.cn/fmcc.html fmcc bvso, http://highqual.cn/rodentcontrol.html rodent control >:], http://highqual.cn/fakegrass.html fake grass 678, http://highqual.cn/hotelqt.html hotel qt 180534, http://highqual.cn/socorroisd.html socorro isd :DD, http://highqual.cn/nightlikethis.html night like this 44623,


CategoryCategory

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