TICKscript specification
Introduction
The TICKscript language is an invocation chaining language used to define data processing pipelines.
Notation
The syntax is specified using Extended Backus-Naur Form (“EBNF”). EBNF is the same notation used in the Go programming language specification, which can be found here.
Production = production_name "=" [ Expression ] "." .
Expression = Alternative { "|" Alternative } .
Alternative = Term { Term } .
Term = production_name | token [ "…" token ] | Group | Option | Repetition .
Group = "(" Expression ")" .
Option = "[" Expression "]" .
Repetition = "{" Expression "}" .Notation operators in order of increasing precedence:
| alternation
() grouping
[] option (0 or 1 times)
{} repetition (0 to n times)Grammar
The following is the EBNF grammar definition of TICKscript.
unicode_char = (* an arbitrary Unicode code point except newline *) .
digit = "0" … "9" .
ascii_letter = "A" … "Z" | "a" … "z" .
letter = ascii_letter | "_" .
identifier = ( letter ) { letter | digit } .
boolean_lit = "TRUE" | "FALSE" .
int_lit = "1" … "9" { digit }
letter = ascii_letter | "_" .
number_lit = digit { digit } { "." {digit} } .
duration_lit = int_lit duration_unit .
duration_unit = "u" | "µ" | "ms" | "s" | "m" | "h" | "d" | "w" .
string_lit = `'` { unicode_char } `'` .
star_lit = "*"
regex_lit = `/` { unicode_char } `/` .
operator_lit = "+" | "-" | "*" | "/" | "==" | "!=" |
"<" | "<=" | ">" | ">=" | "=~" | "!~" |
"AND" | "OR" .
Program = Statement { Statement } .
Statement = Declaration | Expression .
Declaration = "var" identifier "=" Expression .
Expression = identifier { Chain } | Function { Chain } | Primary .
Chain = "@" Function | "|" Function { Chain } | "." Function { Chain} | "." identifier { Chain } .
Function = identifier "(" Parameters ")" .
Parameters = { Parameter "," } [ Parameter ] .
Parameter = Expression | "lambda:" LambdaExpr | Primary .
Primary = "(" LambdaExpr ")" | number_lit | string_lit |
boolean_lit | duration_lit | regex_lit | star_lit |
LFunc | identifier | Reference | "-" Primary | "!" Primary .
Reference = `"` { unicode_char } `"` .
LambdaExpr = Primary operator_lit Primary .
LFunc = identifier "(" LParameters ")"
LParameters = { LParameter "," } [ LParameter ] .
LParameter = LambdaExpr | Primary .Was this page helpful?
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