V8 Engine repeated #include → supports function, var but not let and const

[Patrick C]

Context
Before the V8 engine, variables could only be declared with var.
V8 adds declaration with const and let.

Issue
jseeFile1
jseeFile2 ← #include jseeFile1
jseeFile3 ← #include jseeFile1, #include jseeFile2

In jseeFile3 EmEditor’s #include directive is smart enough not to include jseeFile1 twice, but only with respect to declarations with function and var.

It appears that EmEditor’s #include directive has not yet been updated to treat declarations with const and let the same way as it treats var.

Detailed example
jseeFile1_params.jsee

#language = "V8"
#async = "off"

var defaultVal = "Hello!";   // «const» & «let» fail; «var» works

jseeFile2_functions.jsee

#language = "V8"
#async = "off"
#include "jseeFile1_params.jsee"

function greet(greeting = defaultVal) {
  alert(greeting);
}

jseeFile3_main.jsee

#language = "V8"
#async = "off"
#include "jseeFile1_params.jsee"
#include "jseeFile2_functions.jsee"

status = "defaultVal = " + defaultVal;
greet();

In jseeFile1_params.jsee
Changing var defaultVal = "Hello!";
To let defaultVal = "Hello!";
or const defaultVal = "Hello!";
results in jseeFile3_main.jsee no longer working.

In this simple example the workaround is to not include jseeFile1 in jseeFile3_main, but this can get tricky once the dependencies get more complex.

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