62 lines
1.3 KiB
Plaintext
62 lines
1.3 KiB
Plaintext
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pico-8 cartridge // http://www.pico-8.com
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version 41
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__lua__
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-- the parser
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parser = {}
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mknew(parser)
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-- calls parse_into with a nop
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-- emit function.
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function parser:parse(str)
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self:parse_into(str, function() end)
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end
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-- read a file of commands and
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-- execute them, emitting the
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-- results from each call into
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-- `emit` as a table per row.
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--
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-- a "command" is a method on
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-- self. a row alternates
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-- commands with args. when
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-- calling a command, it also
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-- gets a table of previous
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-- results as the first arg.
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-- args are split on ','.
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function parser:parse_into(str, emit)
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for row in all(split(str, "\n")) do
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local prev = {}
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local sectors = split(row, ":")
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for i=1,#sectors,2 do
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local x = self[sectors[i]](self, prev, usplit(sectors[i+1]))
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if (x) add(prev, x)
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end
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emit(prev)
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end
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end
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-- saves prev[sel] as self.name.
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-- if sel is unspecified, saves
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-- all of prev (as a table).
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function parser:saveas(prev, name, sel)
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self[name] = sel and prev[sel] or prev
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end
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-- returns its args, ignoring
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-- prev. Used to stuff things
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-- into prev. args are packed
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-- if there's multiple.
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function parser:val(_, ...)
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local ret := pack(...)
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if (#ret == 1) return ret[1]
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return ret
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end
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function parser:bind(_, fn, ...)
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local f = self[fn]
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return function()
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f(...)
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end
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end
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