parse                  package:base                  R Documentation

Parse Expressions

Description:

     `parse' returns the parsed but unevaluated expressions in a list. 
     Each element of the list is of mode `expression'.

Usage:

     parse(file = "", n = NULL, text = NULL, prompt = "?", white = FALSE)

Arguments:

    file: a connection, or a character string giving the name of a file
          or a URL to read the expressions from. If `file' is `""' and
          `text' is missing or `NULL' then input is taken from the
          console.

       n: the number of statements to parse.  If `n' is negative the
          file is parsed in its entirety.

    text: character. The text to parse, quoted.

  prompt: the prompt to print when parsing from the keyboard. `NULL'
          means to use R's prompt, `options("prompt")[[1]]'.

   white: if `TRUE' then any white space separates expressions
          otherwise only newlines or semicolons do.

Details:

     All versions of R accept input from a connection with end of line
     marked by LF (as used on Unix), CRLF (as used on DOS/Windows) or
     CR (as used on Mac).  The final line can be incomplete, that is
     missing the final EOL marker.

See Also:

     `scan', `source', `eval', `deparse'.

Examples:

     cat("x <- c(1,4)\n  x ^ 3 -10 ; outer(1:7,5:9)\n", file="xyz.Rdmped")
     # parse 3 statements from the file "xyz.Rdmped"
     parse(file = "xyz.Rdmped", n = 3)
     unlink("xyz.Rdmped")

