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23 lines
679 B
Racket
23 lines
679 B
Racket
7 years ago
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#lang brag
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top : @statement*
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statement : (assignment | expr | return) /";" | if | while
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assignment : /"var" id /"=" expr
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@expr : comparison
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comparison : [comparison ("!=" | "==")] sumlike
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sumlike : [@sumlike /"+"] value
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@value : id | INTEGER | STRING | object | func-def | func-app | increment
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increment : id /"++"
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object : /"{" @kvs /"}"
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kvs : [kv (/"," kv)*]
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/kv : expr /":" expr
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func-def : /"function" /"(" ids /")" @block
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/ids : [id (/"," id)*]
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@id : ID | dotted-id
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dotted-id : DOTTED-ID
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block : /"{" @statement* /"}"
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return : /"return" expr
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func-app : id /"(" @exprs /")"
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exprs : [expr (/"," expr)*]
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if : /"if" /"(" expr /")" @block
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while : /"while" /"(" expr /")" @block
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