Scripting Migrations

v1 to v2

The version 2 of our scripting language comes with the following changes:

• Multiple sequences can now be defined.

• Sequences can now be used with strategy scripting.

• Sequences are no longer constructed from one condition per line, instead the new then operator should be used.

• New {any_inactive_step} placeholder returning true if any step but the active one is true, can only be used for invalidation

• Actions @invalidate and @set_step have been replaced with their corresponding methods.

• Actions no longer require to have the argument name specified:

before: @label(y = "{close}", text = "hello")

now: @label({close}, "hello")

• Actions argument values no longer requires to be in between quotes/double quotes.

• y argument for @label and @line actions now support historical referencing.

• Action @valuewhen now accepts a new reference argument allowing to reuse the captured value in other conditions/actions.

• Removed @filter action.

Migrating from v1 to v2

Defining Sequences

Scripted alerts using a sequence previously separated steps by linebreaks:

{close} > {open} // Step 1

{close} crossover {close[9]} // Step 2

{volume} crossover 10000 // Step 3

Now sequences can be defined inline using the new then operator as follows:

{close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000

Invalidating Sequences

Previously sequences were invalidated using the @invalidate action:

{close} > {open} // Step 1

{close} crossover {close[9]} // Step 2

{volume} crossover 10000 // Step 3

@invalidate() = {close} < {open} // invalidate if closing price is lower than open

This can now be done inline using the new operator !:

{close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000 ! {close} < {open} 

Or using the new method invalidate as long as an udp is defined for the sequence:

{my_sequence}.invalidate() = {close} < {open} // Invalidation of {my_sequence}

{my_sequence} = {close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000

If your invalidation setup only affected specific steps such that you had:

@invalidate(step= 1,2) = {close} < {open} // invalidate if closing price is lower than open and active steps are the second one or third one

Then you can reuse a similar setup:

{my_sequence}.invalidate(step= 1,2) = {close} < {open} // Invalidation of {my_sequence}

Changing Step

Previously users could change the active step of a sequence using the @set_step action:

{close} > {open} // Step 1

{close} crossover {close[9]} // Step 2

{volume} crossover 10000 // Step 3

@set_step(0) = {close} < {open} // Set step to 0 if closing price is lower than open

Now this can be done with the set_step action:

{my_sequence}.set_step(0) = {close} < {open} // Set step to 0 if closing price is lower than open

{my_sequence} = {close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000

The value argument still accept increments and decrements.

Accessing a sequence active step

Previously users could access the active step of a sequence (the step subject to evaluation) using the {step} placeholder.

Due to the possibility with version 2 of hacing multipe sequences in a single script, the active step can be obtained from a defined UDP for the sequence:

{my_sequence} = {close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000

// Get the active step for {my_sequence}
{my_sequence.step}.

Accessing a sequence elapsed bars since new step

Previously users could access the numbers of bars elapsed since a last step was true or invalidation of the sequence using the {barssince_step} placeholder.

Due to the possibility with version 2 of hacing multipe sequences in a single script, the active step can be obtained from a defined UDP for the sequence:

{my_sequence} = {close} > {open} then {close} crossover {close[9]} then {volume} crossover 10000

// Get the number of bars ellapsed since a last step was true or invalidation for {my_sequence}
{my_sequence.barssince_step}

Filtering each steps with @filter

Previously users could apply a condition to all steps of a sequence with a single usage of the @filter action as follows:

{close} > {open} // Step 1

{close} crossover {close[9]} // Step 2

{volume} crossover 10000 // Step 3

@filter() = {volume} > 5000 // Test for all steps if volume is above 5000

This can be done by having a UDP associated to this filter condition and using the and operators with it:

{vol_filter} = {volume} > 5000 
{my_sequence} = {close} > {open} and {vol_filter} then {close} crossover {close[9]} and {vol_filter} then {volume} crossover 10000 and {vol_filter}