QCAD.org Forum

Posted: **Sat Sep 06, 2025 5:36 am**

Related to a script code in this topic

This most simple if-else clause fails for GE but not as script file using 'Run Script' (XC):

Code: Select all

var document = EAction.getDocument();

if (!isNull(document) && document.hasSelection()) {
    // Do something meaningful:
    EAction.handleUserInfo("Done something meaningful.");
}
else {
    // Warn user on critical faults:
    EAction.handleUserWarning("No document or no selection.");
}

A command string is concatenated until the count of all open brackets ( & { & [ equals the count of all closing brackets ) & } & ].
The above code is thus evaluated in 3 steps:
- eval("var document = EAction.getDocument();")
- eval("if (...) {...}")
- eval("else {...}") Resulting in a: Syntax error
In what other condition would else apply if evaluated apart from the if clause?

The code below doesn't fail:

Code: Select all

var document = EAction.getDocument();

if (1 > 0) {
    if (!isNull(document) && document.hasSelection()) {
        // Do something meaningful:
        EAction.handleUserInfo("Done something meaningful.");
    }
    else {
        // Warn user on critical faults:
        EAction.handleUserWarning("No document or no selection.");
    }
}

Evaluated in two steps:
- eval("var document = EAction.getDocument();")
- eval("if (1>0) {...}")

The "if (1 > 0) {...}" fix does work when enclosing the specific 71 lines of code in the related topic.
But you can't stretch it indefinitely.

Also remark that brackets in plain text or comments are accounted for just the same.

Code: Select all

// This won't run because of the Sad smiley :( 
var document = EAction.getDocument();

if (!isNull(document) && document.hasSelection()) {
    // Do something meaningful:
    EAction.handleUserInfo("Done something meaningful.");
}
else {
    // Warn user on critical faults:
    EAction.handleUserWarning("No document or no selection.");
}

Not evaluated yet, the Shell expect more lines including one with the associated closing bracket of the smiley.
Add that bracket in a comment otherwise it results in a: Syntax error

Include brackets in plain text intended for a string using their character codes.

Another solution is to include your code as a block starting with '{' and ending with '}'
And yet another solution but much slower is defining the block as a function and calling this function.

Code: Select all

function main() {
    ....
};

main();

The last 2 solutions rely on the fact that the block text or the function text is only evaluated after the last closing bracket.
Just the same as with the dummy "if (1>0) {...}" clause.

Regards,
CVH

QCAD.org Forum

Script Shell (GE) fails for the simplest if-else clause

Script Shell (GE) fails for the simplest if-else clause