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ff (version 4.5.0)

hiparse: Hybrid Index, parsing

Description

hiparse implements the parsing done in Hybrid Index Preprocessing in order to avoid RAM for expanding index expressions. Not to be called directly

Usage

hiparse(x, envir, first = NA_integer_, last = NA_integer_)

Value

undefined (and redefined as needed by as.hi.call)

Arguments

x

an index expression, precisely: call

envir

the environemtn in which to evaluate components of the index expression

first

first index position found so far

last

last index position found so far

Author

Jens Oehlschlägel

Details

This primitive parser recognises the following tokens: numbers like 1, symbols like x, the colon sequence operator : and the concat operator c. hiparse will Recall until the index expression is parsed or an unknown token is found. If an unknown token is found, hiparse evluates it, inspects it and either accepts it or throws an error, catched by as.hi.call, which falls back to evaluating the index expression and dispatching (again) an appropriate as.hi method. Reasons for suspending the parsing: if the inspected token is of class 'hi', 'ri', 'bit', 'bitwhich', 'is.logical', 'is.character', 'is.matrix' or has length>16.

See Also

hi, as.hi.call