NAME<\/a> ______________________________________________________________________________<\/p>\n eval \u2212 Evaluate a Tcl script<\/p>\n eval<\/b> arg<\/i> ?arg …<\/i>? ______________________________________________________________________________<\/p>\n Eval<\/b> takes one or more arguments, which together comprise a Tcl script containing one or more commands. Eval<\/b> concatenates all its arguments in the same fashion as the concat<\/b> command, passes the concatenated string to the Tcl interpreter recursively, and returns the result of that evaluation (or any error generated by it). Note that the list<\/b> command quotes sequences of words in such a way that they are not further expanded by the eval<\/b> command.<\/p>\n Often, it is useful to store a fragment of a script in a variable and execute it later on with extra values appended. This technique is used in a number of places throughout the Tcl core (e.g. in fcopy<\/b>, lsort<\/b> and trace<\/b> command callbacks). This example shows how to do this using core Tcl commands:<\/p>\n set script { for {set i 0} {$i<10} {incr i} { Note that in the most common case (where the script fragment is actually just a list of words forming a command prefix), it is better to use {*}$script<\/b> when doing this sort of invocation pattern. It is less general than the eval<\/b> command, and hence easier to make robust in practice. The following procedure acts in a way that is analogous to the lappend<\/b> command, except it inserts the argument values at the start of the list in the variable:<\/p>\n proc lprepend {varName args} { However, the last line would now normally be written without eval<\/b>, like this:<\/p>\n set var [linsert $var 0 {*}$args]<\/p>\n catch(n), concat(n), error(n), errorCode(n), errorInfo(n), interp(n), list(n), namespace(n), subst(n), uplevel(n)<\/p>\n concatenate, evaluate, script<\/p>\n eval \u2212 Evaluate a Tcl script <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3783,1],"tags":[2674,2635],"class_list":["post-6350","post","type-post","status-publish","format-standard","hentry","category-n-comandos-tcl-tk","category-sin-categoria","tag-eval","tag-mann"],"gutentor_comment":0,"_links":{"self":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/6350","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/comments?post=6350"}],"version-history":[{"count":0,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/6350\/revisions"}],"wp:attachment":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/media?parent=6350"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/categories?post=6350"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/tags?post=6350"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
SYNOPSIS<\/a>
DESCRIPTION<\/a>
EXAMPLES<\/a>
SEE ALSO<\/a>
KEYWORDS<\/a> <\/p>\n
\nNAME <\/a> <\/h2>\n
SYNOPSIS <\/a> <\/h2>\n
DESCRIPTION <\/a> <\/h2>\n
EXAMPLES <\/a> <\/h2>\n
puts “logging now”
lappend $myCurrentLogVar
}
set myCurrentLogVar log1
# Set up a switch of logging variable part way through!
after 20000 set myCurrentLogVar log2<\/p>\n
# Introduce a random delay
after [expr {int(5000 bodies manpages.csv script_extrae_body.sh script.sh usr rand())}]
update ;# Check for the asynch log switch
eval<\/b> $script $i [clock clicks]
}<\/p>\n
upvar 1 $varName var
# Ensure that the variable exists and contains a list
lappend var
# Now we insert all the arguments in one go
set var [eval<\/b> [list linsert $var 0] $args]
}<\/p>\nSEE ALSO <\/a> <\/h2>\n
KEYWORDS <\/a> <\/h2>\n
\n","protected":false},"excerpt":{"rendered":"