Espruino Internals

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Gordon

And then...

Byte	Name	STRING	STR_EXT	NAME_STR	NAME_INT	INT	DOUBLE	OBJ/FUNC/ARRAY	ARRAYBUFFER	FLAT_STR	NATIVE_FUNC
0 - 3	varData	data	data	data	data	data	data	nativePtr	size	size	nativePtr
4 - 5	next	-	data	next	next	-	data		format	-	argTypes
6 - 7	prev	-	data	prev	prev	-	data		format	-	-
	8 - 9	refs	refs	data	refs	refs	refs	refs	refs	refs	refs
	10-11	first	-	data	child	child	-	-	first	stringPtr	-
	12-13	last	nextPtr	nextPtr	nextPtr	-	-	r?	last	-	nextPtr
	14-15	Flags	Flags	Flags	Flags	Flags	Flags	Flags	Flags	Flags	Flags

I saw it already last week, but I can not tell the difference among NAME, INT, NAME_INT, NAME_INT_INT? also STRING and STR_EXT.

You'd have to look further into the code - look at the comments here: https://github.com/espruino/Espruino/blob/master/src/jsutils.h#L254

And in the table, what is the difference between “varData” and “data”, “nextPtr” and “next”?

The 2nd column 'Name' is just the name of the field - it doesn't really mean anything other than being descriptive (and possibly the name of the variable)

And what does the “child” means, it is firstChild?

Some variable types have just a single child. See jsvHasSingleChild

digitalWrite([A5,A6],0x11), I see the function about this is : https://github.com/espruino/Espruino/blob/4e9f34831ff9f200cc5e261c30a2af9f145b980c/src/jswrap_io.c#L233

In the function, jsvLock(pinName) uses jsvGetAddressOf(pinName), and jsvGetAddressOf(pinName) just return &jsVars[ref-1]. Does it mean all variable are stored in jsVar[JSVAR_CACHE_SIZE], including local variable and global variable, like Serial1?

Yes. jswrapper may 'make' the global variable if it doesn't already exist though.

If it is, what is the function of the jsvSkipName(pinNamePtr). I see the definition of the jsvSkipName(), It is : https://github.com/espruino/Espruino/blob/4e9f34831ff9f200cc5e261c30a2af9f145b980c/src/jsvar.c#L1542

I don’t understand that “if a is a name ” . What does “a name” mean?

see 'lvalue' on wikipedia - a Name in Espruino is one of those - a variable that is a pointer to another. For instance in a = 1, 1 is not a name (it cannot be written) but a is. However, after assignment a will point to the value 1.

What is the effect of the function indeed ?

It skips the name. In the case above, 'jsvSkipName(a)' would skip over 'a' and return 1.

And what is the relationship of JsExecIfo->root and jsVar[JSVAR_CACHE_SIZE]

JsExecIfo->root is basically the value of the 'global' variable. jsVar[JSVAR_CACHE_SIZE] holds all variables, including 'global'.

Espruino Internals

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