(Tcl) Demonstrates how to Handle Large Integers in JSON

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Demonstrates how to handle large integers in JSON. (Integers larger than what can fit in a 32-bit signed integer.)

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load ./chilkat.dll

# Let's say your JSON has this:

# {
# 	"id": 20000000001234567
# }

set json [new_CkJsonObject]

set success [CkJsonObject_LoadFile $json "qa_data/json/large_int.json"]
if {$success == 0} then {
    puts [CkJsonObject_lastErrorText $json]
    delete_CkJsonObject $json
    exit
}

# The integer is too large for a 32-bit signed integer that is returned by IntOf.
# The result will be something that wrapped around and could be negative.
# In this case it would be: -543893881
set id [CkJsonObject_IntOf $json "id"]
puts "id: $id"

# The solution is to read the integer value as a string, and then use the features in your programming language
# to convert from a string to a 64-bit integer.
# 
# Alternatively, you may wish to simply hold the value as a string.  If, for example, the integer simply references
# an order ID, an account ID, etc., then there's no need to convert to an integer value.  You're not going to be doing
# mathematical operations on it anyway.  This is usually the case for large integers -- they typically exist
# in JSON as an account ID.

# You can get any JSON value as a string:
set accountId [CkJsonObject_stringOf $json "id"]
puts "accountId: $accountId"

# Sample output:

# id: -543893881
# accountId: 20000000001234567

delete_CkJsonObject $json