wiki/debug.variable.md

In ProvTools/provDebugR: A Time-Travelling Debugger

For each variable queried, debug.variable returns a data frame of all instances (data nodes) of that variable.

Each data frame contains the following columns: value The value of the variable. container The type of the container of the variable. dimension The size of the container. type The data type(s) contained within the container. scriptNum The script number the variable is associated with. scriptName The name of the script the variable or file is associated with. startLine The line number the variable is associated with. code The code this variable is associated with.

Usage

The function signature for debug.variable is:

debug.variable(..., val.type = "all", script.num = "all", all = FALSE)

The parameters of this function are: ... The variable names to be queried. val.type If not "all", this filters the results to contain only instances where the valType (container or type) has the queried type. script.num The script number of the queried variables. Defaults to "all". all If TRUE, results for all variables of the specified script will be returned.

Only 1 script number and/or valType may be queried per function call.

This function may be called only after initialising the debugger using either prov.debug, prov.debug.run, or prov.debug.file. For example:

prov.debug.run("myScript.R")
debug.variable(x)
debug.variable(all = TRUE)
debug.variable("a", b, "x", val.type = "logical")
debug.variable("a", "b", x, script.num = 3)

Output Examples

Let myScript.R be the following:

a <- "one"
a <- "two"
a <- 1L
a <- 2L

b <- 3L
b <- 4L
b <- "five"

1. Checking for all instances of a variable

The result for debug.variable("a") is:

$a
  value container dimension      type scriptNum scriptName startLine       code
1 "one"    vector         1 character         1 myScript.R         1 a <- "one"
2 "two"    vector         1 character         1 myScript.R         2 a <- "two"
3     1    vector         1   integer         1 myScript.R         3    a <- 1L
4     2    vector         1   integer         1 myScript.R         4    a <- 2L

2. Checking for all instances of a variable with a certain type

The result for debug.variable("a", val.type = "integer") is:

$a
  value container dimension    type scriptNum scriptName startLine    code
1     1    vector         1 integer         1 myScript.R         3 a <- 1L
2     2    vector         1 integer         1 myScript.R         4 a <- 2L

3. Checking for all instances of multiple variables

When multiple variables are queried, the results for each variable are bound together in a list, resulting a list of data frames.

The result for debug.variable("a","b") is:

$a
  value container dimension      type scriptNum scriptName startLine       code
1 "one"    vector         1 character         1 myScript.R         1 a <- "one"
2 "two"    vector         1 character         1 myScript.R         2 a <- "two"
3     1    vector         1   integer         1 myScript.R         3    a <- 1L
4     2    vector         1   integer         1 myScript.R         4    a <- 2L

$b
   value container dimension      type scriptNum scriptName startLine        code
1      3    vector         1   integer         1 myScript.R         6     b <- 3L
2      4    vector         1   integer         1 myScript.R         7     b <- 4L
3 "five"    vector         1 character         1 myScript.R         8 b <- "five"

4. Checking for all instances of a multiple variables with a certain type

The result for debug.variable("a", "b", val.type = "integer") is:

$a
  value container dimension    type scriptNum scriptName startLine    code
1     1    vector         1 integer         1 myScript.R         3 a <- 1L
2     2    vector         1 integer         1 myScript.R         4 a <- 2L

$b
  value container dimension    type scriptNum scriptName startLine    code
1     3    vector         1 integer         1 myScript.R         6 b <- 3L
2     4    vector         1 integer         1 myScript.R         7 b <- 4L

ProvTools/provDebugR documentation built on April 29, 2021, 7:22 p.m.