help confirm
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Title
[P] confirm -- Argument verification
Syntax
confirm existence string
confirm [new] file filename
confirm [ numeric | string | date ] format string
confirm names names
confirm [integer] number string
confirm matrix string
confirm scalar string
confirm [ new | numeric | string | type ] variable varlist [, exact]
where type is { byte | int | long | float | double | str# }
Description
confirm verifies that the arguments following confirm ... are of the
claimed type and issues the appropriate error message and nonzero return
code if they are not.
confirm is useful in do-files and programs when you do not want to bother
issuing your own error message. confirm can also be combined with
capture to detect and handle error conditions before they arise; see [P]
capture.
See [P] confirm for a complete description of this command.
Option
exact specifies that a match be declared only if the names specified in
varlist match. By default, names that are abbreviations of variables
are considered to be a match.
Examples
. confirm file `"c:\data\mydata.dta"'
. confirm numeric variable price trunk rep78
You are writing a command that performs some action on each of the
variables in the local macro varlist. The action should be different for
string and numeric variables. The confirm command can be used here in
combination with the capture command to switch between the different
actions:
foreach v of local varlist {
capture confirm string variable `v'
if !_rc {
action for string variables
}
else {
action for numeric variables
}
}
An alternative solution using inline expansion of the extended macro
function :type (see local) reads
foreach v of local varlist {
if substr("`:type `v''",1,3) == "str" {
action for string variables
}
else {
action for numeric variables
}
}
Also see
Manual: [P] confirm
Help: [P] capture
