Nasal library/debug

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This page contains documentation for the debug namespace in Nasal. This namespace provides various useful APIs for debugging Nasal code. The debug namespace is sourced from fgdata/Nasal/debug.nas.

Functions

attributes()

debug.attributes(p[, verbose[, color]]);

Returns a string showing the attributes of the node, in the form (type[, attr[, Lnum[, #refs]]). See the table below for explanation.

Data	Meaning
type	Type of node as returned by props.Node.getType() .
attr	Various attribute flags, see props.Node.getAttribute() . "r" = read protected, "w" = write protected, "R" = trace read, "W" = trace write, "A" = archive, "U" = userarchive, "P" = preserve, and "T" = tied.
num	Number of listeners, if any.
refs	This argument will be shown if verbose is true. Tells the number of references to the node. Note that all nodes have two references by default, but this tells the number of extra references.

p

Mandatory props.Node object.

verbose

Optional bool specifying whether to show the number of times the node is referenced. Defaults to 1 (true).

color

Optional bool specifying whether to output the string with an ANSI color code . Defaults to nil.

Examples

var node = props.globals.getNode("/sim/time/gmt");
print(debug.attributes(node)); # prints "(STRING, AT, #1)" - string, archive, tied, 1 extra ref

var node = props.Node.new();
node.setIntValue(12);
node.setAttribute(17);
print(debug.attributes(node)); # prints "(INT, wR)" - integer, write protected, trace read

var node = props.globals.getNode("/sim/signals/fdm-initialized");
print(debug.attributes(node)); # prints "(BOOL, L6, #16)" - bool, 6 listeners, 16 extra refs

backtrace()

debug.backtrace([desc]);

When called, this function prints the backtrace , also printing the local variables at each level.

desc

Optional extra description to add.

Examples

var myFunc = func(a){
    multiply(a, 2);
}
var multiply = func(x, y){
    debug.backtrace();
}
myFunc(2);

var myFunc = func(a){
    multiply(a, 2);
}
var multiply = func(x, y){
    debug.backtrace("multiply() function");
}
myFunc(2);

bt()

debug.bt([desc]);

Shortcut for backtrace() . See doc there