Try / Catch

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Try / Catch
Handling expected errors and dealing with the result.
The try/catch section is designed to handle expected errors and prevent the program terminating, while also allowing special fail-case behaviour to be run.
It forms a tree structure of two possible branches. One or both of these may be run.
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try:
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    // attempted branch
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catch %Variable%:
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    // failure branch
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Try Block
These must always start with a try effect as the section header. This header has no inputs or options.
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try:
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    print "yes"
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The code in this block will always be attempted. However, it is run with the expectation of failing (an error being thrown.)
The try section must always be followed by a catch section.
Catch Block
These must always follow a try section. The catch %Variable% section accepts a normal variable.
The error will be stored in this variable.
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try:
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    print "always run"
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catch {var}:
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    print "caught the error: " + {var}
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print "continues here"
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The code in this block will be run only if the preceding try-section fails. If no error is thrown, the catch section will not be run.
The catch section will be jumped to after the line that fails
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try:
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    print "hello"
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    assert 1 is 2 // error! jump -> catch
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    print "never run" // this will not be reached.
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catch {var}: // {var} contains the error object
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    print "caught an error: " + {var}
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print "continues here"
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If no error occurs, the catch-section will be skipped.
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try:
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    print "always run"
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catch {var}:
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    print "never run"
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print "continues here"
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Any break instructions will exit this tree entirely (jump to after the catch section finishes.)
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try:
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    print "always run"
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    break section // exits all
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    print "never run"
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catch {var}: // skipped by the break
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    print "never run"
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print "continues here"
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Monitor
Lambda
Last modified 3mo ago
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Contents
Try Block
Catch Block