Cross-parse from an R parse tree into SQL.

Source: R/tokenize_for_sql.R

Cross-parse from an R parse tree into SQL.

tokenize_for_SQL(lexpr, colnames, env = parent.frame())

Arguments

lexpr

item from substitute
colnames

column names of table
env

environment to look for values

Value

sql info: list(presentation, parsed_toks(list of tokens), sql_text, symbols_used, symbols_produced, free_symbols)

Examples


tokenize_for_SQL(substitute(1 + 2), colnames= NULL)

#> $presentation
#> [1] "1 + 2"
#> 
#> $parsed_toks
#> 1 + 2
#> $symbols_used
#> character(0)
#> 
#> $symbols_produced
#> character(0)
#> 
#> $free_symbols
#> character(0)
#> 
tokenize_for_SQL(substitute(a := 3), colnames= NULL)

#> $presentation
#> [1] "a := 3"
#> 
#> $parsed_toks
#> [1] "3"
#> 
#> $symbols_used
#> character(0)
#> 
#> $symbols_produced
#> [1] "a"
#> 
#> $free_symbols
#> character(0)
#> 
tokenize_for_SQL(substitute(a %:=% ( 3 + 4 )), colnames= NULL)

#> $presentation
#> [1] "a %:=% (3 + 4)"
#> 
#> $parsed_toks
#> ( 3 + 4 )
#> $symbols_used
#> character(0)
#> 
#> $symbols_produced
#> [1] "a"
#> 
#> $free_symbols
#> character(0)
#>