Something sweet about DSL — PuzzleScript

I’ve just read at Lambda the Ultimate (one of the must-subscribe blogs) about PuzzleScript:

It is an HTML5-based puzzle game engine that uses a simple language for patterns and substitutions to describe game rules. For example (taken from their introduction), the basic block-pushing logic of a Sokoban game can be given as:

[ > Player | Crate ] -> [ > Player | > Crate ]

This line says that when the engine sees the pattern to the left of ->, it should replace it with the pattern on the right. In this case, the rule can be read as something like: when there is a row or column ([]) that contains a player object (Player) next to (|) a crate object (Crate), and the player is trying to move toward the crate (>), then (->) make the crate move in the same direction.

The introduction given at the PuzzleScript webpage is very informative, full of animations. And those examples bring sweet memories of old games played in the 8-bit era. Take a look yourself!

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Fragments — multi-syntax language?

As an avid reader of old Joel on Software blog I am fully aware of the complain actually any developer can make:

They [people who don’t Get Things Done] will say, “Spreadsheets are really just a special case of programming language,” and then go off for a week and write a thrilling, brilliant whitepaper about the theoretical computational linguistic attributes of a spreadsheet as a programming language. Smart, but not useful.

Quoted from: The Guerrilla Guide to Interviewing.

I would like to be useful but after tinkering with syntax for collections I realized that maybe it is wrong path — one reason is I have only limited ASCII set so it is hard to satisfy all expressions I like to have and make them look nice at the same time. The other is if Skila is supposed to be really multi-purpose language can one syntax fit all the needs? Maybe another approach is required — one language, multiple syntaxes (one could think of the analogy of Java world — one byte code, multiple languages and thus multiple syntaxes).

I am not the first one with this idea, take for example TeX with its environments, once you start math mode all the symbols are treated differently than in the main block. In programming language it might pay off, because when writing general code you would like to be more self explanatory:

1/Math.Pow(x,2.0)

But if you have a function which does only heavy mathematical computation it could be more useful to make a switch:

#math
1/x^2
#end math

Who knows? It is an odd idea, but could be a right vehicle if you would like to have the same semantics but different syntax for given domain, you could say inner DSL.