AlgoBarsX documentation.
Everything the language can do.

AlgoBarsX is the language AlgoBars runs on. You describe a strategy, an indicator or an alert in a few readable lines, and the same script is used by the chart, the backtester, the alerts engine and live automation. There is one definition of what your rule means, so you never rewrite it for a different tool.

There are four kinds of script. The first word of the file says which one it is.

Every script is also translated back into plain English by the compiler, so you can check that it says what you meant. That text is generated from the compiled code. If the English is wrong, the code is wrong.

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1. Open the Terminal in AlgoBars and start a new strategy. You get a working starter script, not a blank page.
2. Replace it with the script below. It buys when a fast average crosses above a slow one, risks 1% of the balance with a 25-pip stop and a target of twice the risk, and closes everything on the opposite cross.

3. Open the description tab. The compiler reads the script back to you:

4. Press Run. A small panel asks what to test on: market, bars, bar type, how far back (1 week to 1 year), lot size and starting balance. The market and bars come filled in from your script, so you are confirming, not retyping.
5. You get results, a report, a chart and a replay. The replay plays the finished test back so you can watch each trade open and close and the balance move. Every run is kept under versions with the code that produced it, so you can always go back.
6. Change fast or the stop and run again. Nothing is lost by trying.

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One script that touches the header, inputs, constants, state, history, another bar size, confirmations, a rule with timing, a managed order, an event and a plot. Copy it into the Terminal and start deleting what you do not need.

For the long version, see the Language Tour example, which uses nearly every construct in the language.

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A script reads from top to bottom in five parts. Only the header is required.

• Blocks are indented with spaces. A line ending in a colon opens a block, and the lines under it are indented. Tabs are an error (AS0003).
• Comments start with # and run to the end of the line.
• The optional first line algobarsx 1 names the language version the script was written for.
• Line breaks inside ( ), [ ] or { } are ignored, so long expressions can span lines there.
• Names are case-sensitive. A short list of words is reserved, such as when, on, if, state and input. The full list is in the grammar.

At each bar close the runtime works in a fixed order: fills and management inside the bar, then on fill and on exit, then calculations, then confirmations and sequences, then rules in script order, then exports and drawing. Orders your rules create take effect from the next bar. See E21 and E1.

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This is a real run of the importer on a small Pine Script script. The result compiles. 8 lines were read: 5 carried over exactly, 2 were adapted and 2 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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This is a real run of the importer on a small MQL4 and MQL5 script. The result compiles. 11 lines were read: 6 carried over exactly, 6 were adapted and 2 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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This is a real run of the importer on a small NinjaScript script. The result compiles. 26 lines were read: 5 carried over exactly, 1 were adapted and 4 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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This is a real run of the importer on a small EasyLanguage script. The result compiles. 6 lines were read: 3 carried over exactly, 3 were adapted and 1 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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This is a real run of the importer on a small thinkScript script. The result compiles. 8 lines were read: 7 carried over exactly, 1 were adapted and 0 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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This is a real run of the importer on a small Python script. The result compiles. 5 lines were read: 4 carried over exactly, 1 were adapted and 0 came back as decisions for you.

Line by line

How the ideas translate

Names the importer translates for you

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Most mistakes in trading code are unit mistakes. AlgoBarsX makes the unit part of the value, and the compiler checks it.

A stop written as a bare number is caught before anything runs: “stop 25 has no unit. Did you mean 25 pips?” (AS0302). A price level and a distance are different things, and the compiler knows which one an option expects.

Text with live values

Text in double quotes can include any expression in braces, with an optional format after a colon. Write {{ for a literal brace.

Units follow the value, not the text

The engine works a unit out from the code. It does not look for the word “pips” in what you typed.

• A price with a distance taken off it is still a price. stop: lowest(low, 10) - 3 pips is a level on the chart.
• One price taken from another is a distance.
• A distance stays a distance when you scale it, as in atr(14) * 2.
• A unit held in an input travels with it. After input risk = 1%, the order risk: risk risks one percent, exactly as if you had written 1%.

All eight units are listed under Units.

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close is not one number. It is a series with a value on every bar. Square brackets read earlier bars: close[1] is the previous bar's close. A value at a bar never depends on a later bar, and the test suite proves it by rewriting the future and checking the past did not move.

• was is true if a condition was true at some point in recent bars. held is true if it has been true for consecutive bars.
• crosses_above, crosses_below and crosses detect crossings. starts and ends are true on the bar a condition becomes true or stops being true.
• bars_since counts bars since a condition was last true.
• Reading further back than the data goes gives na. nz supplies a fallback.
• Reading forward is an error, not a bug waiting to happen: “close[-1] would read a future bar. History counts back from the current bar: close[1] is the previous bar.” (AS0203)
• Indicator calls update on every bar, even when their line sits in a branch that did not run, so a reading is never stale.

Built-in price series: open high low close volume time hl2 hlc3 ohlc4, plus facts about the bar such as bar.index, bar.confirmed and bar.range. See Bar variables.

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Time variables available everywhere: hour, minute, day_of_week and time_of_day.

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An input becomes a setting in the script's panel. Its type comes from its default value, so input risk = 1% is a percent and input higher_tf = 4h is a bar size. A const is fixed.

An input nobody reads is flagged as a hint (AS0601).

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A plain assignment such as trend_up = close > ema(close, 50) is worked out again on every bar. A state value is set once and keeps whatever you last put in it, which is how you count things or remember a price.

You can annotate a type when the default does not say enough: state last_entry: price = na.

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• if / elif / else choose between blocks.
• for x in list and for i in 0..50 loop. break and continue work as you expect.
• match picks a branch by value, which reads well with an enum.

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• fn defines a pure function. It calculates and returns a value.
• action fn may place orders, so it can only be called where orders are allowed. A plain fn that tries to trade is an error (AS0403).
• type defines a record with named, typed fields and optional defaults. enum defines a fixed set of names.
• Parameters can have types and defaults: fn f(source: series<number> = close, length: int = 20) -> number.

Lists and lambdas

Lists support push, pop, remove, filter, map, sort_by, keep_last, first, last, len and contains, plus the aggregates sum, mean, min and max. A lambda is written x => expression.

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Every setting, with its type and default:

Limits are checked when an entry fills, not when it is placed (E19). With trade_only, entries are only created inside the listed sessions, while exits and management carry on outside them (E22). The named sessions are sydney, tokyo, asia, frankfurt, london and new_york.

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A rule is when <condition> [modifiers]: followed by what to do. Name a rule with as to read its counters later, such as long_entry.triggers.

Modifiers say when a rule may fire, on the rule itself, so there are no counters to build by hand:

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A confirmations block lists named conditions and how many must agree: require: all or require: at least N. It gives you .passed to use in a rule.

The backtest report breaks trades down by which confirmations agreed, so you can see which ones earn their place.

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A sequence waits for its steps in order, within a number of bars. Later steps can refer to the bar where an earlier step happened, such as sweep.high. reset_if abandons the attempt. The sequence gives you .completed.

Examples: Sweep and Reclaim, Renko Pullback, State Machine Momentum.

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• buy and sell with no limit: or entry stop: are market orders. They fill at the next bar's open (E1).
• buy limit: price places a pending limit order. buy stop: price places a pending stop order, and its protective stop is then stop_loss:.
• expires: cancels a pending order after a number of bars or a length of time (E17).
• ghost: true keeps the stop and target off the broker. AlgoBars enforces them instead.
• tag: labels an order and its trade, so you can close, cancel or report on a group.
• close, close_all, modify and cancel act on open trades and pending orders.

What happens when a signal arrives opposite an open trade is the header setting opposite: ignore (the default), close, reverse or hedge (E18).

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Give an order a risk: as a percent of the balance or as money, and a stop. The size is worked out for you:

size = risk amount ÷ (stop distance × contract size × quote-to-account rate)

It is rounded down to the lot step and held between the market's minimum and maximum lot. If the minimum lot would carry more than you asked for, the trade still opens at the minimum lot and is marked “above requested risk” with the risk it actually carries (E11).

• Distances in pips, points or R are measured from the actual fill price, so a gap moves the stop and target with the entry (E9).
• A risk-based order with no stop is an error: “Risk-based size needs a stop to measure risk from.” (AS0304)
• size_for tells you the lot size an entry would use, without placing it.
• You can also size directly with size: 1 lot.

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Management is written under the order it belongs to, as an indented block after the order line.

You can also manage trades from anywhere with a loop over trades.open(...), using close and modify. Example: Active Trade Manager.

Rules about a trade that is still open

An open trade knows how long it has been open and where it stands. trades.last() is the trade being held when there is one, bars_open counts its bars, and r is its result so far measured against its own risk.

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• max_daily_loss: at each bar close, the day's closed profit plus open profit is compared with the limit. When it is reached, all trades close and pending orders are cancelled at the next bar's open, and new entries are rejected until the next UTC day.
• max_drawdown works the same way against the highest equity reached, and pauses the deployment until you resume it.
• max_open, max_open_per_side, pyramiding, max_total_risk and min_distance reject an entry, with a reason, at the moment it would fill.

The rule is E20. You can also write your own guard as an ordinary rule:

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on tick needs a script that evaluates on ticks (AS0404). See Bar close or every tick.

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By default a script runs after each bar closes. With evaluate: tick it runs at every point of the price path, and market orders fill at the price that triggered them.

• Inside a forming bar, prices are live and indicators are not. close, high and low move with the tick, while indicator values stay as they were at the last bar close. Nothing repaints.
• bar.confirmed is false during a tick and true at the close.
• In a backtest, the 1-minute bars inside each bar supply the price path. When a bar has no finer data stored, its own path is used and the run is labelled “approximate intrabar”, listing the bars affected.

Rules: E2 and E6.

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• bars reads another bar size, another symbol, or both. A higher bar's value appears only once its candle has closed, so a 5-minute rule cannot peek at a 4-hour bar early.
• intrabar reads the finer bars inside the current one. close_of is a shortcut for another symbol's close.
• Many functions take on: to calculate on another set of bars, such as atr(14, on: gold).
• data.coverage tells a script how much data it actually has, and whether it is exact.

Several markets in one strategy

Full example: EURUSD and GBPUSD Mean Reversion. Orders take market: to say which symbol they are for.

Other bar types

The header's bars: accepts more than a time: renko, heikin_ashi, range and xray.

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Everything in a report is derived from the trades the engine actually filled and the equity at each bar close, so any number can be traced back to a trade. Costs are never added or assumed: profit is the price difference (E12).

How it went

What it cost

How the trades behaved

Breakdowns

By the rule that opened the trade, by how the trade ended, by the confirmations that agreed, by side, by tag and by month. Name your rules with as and tag your orders, and these tables become much more useful.

Labels worth noticing

• Above requested risk: the minimum lot carried more risk than the order asked for (E11).
• Approximate intrabar: a tick-evaluated run had no finer data for some bars, which are listed (E2).
• Unfilled: a market order created on the last bar of the test (E1).

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Deploying a strategy runs the same script on a demo or live account. The runner evaluates each closed bar, hands out instructions, and waits to be told what actually happened.

• The broker decides fills. A backtest may decide a fill itself. Live, a trade exists only once the broker has confirmed it, and an instruction is never sent twice.
• Restarts are safe. Open trades and their management, rule counters, sequences part way through and pending orders live in a snapshot. After a restart the runner replays recent bars to warm the indicators back up and continues where it left off, so a restart cannot quietly abandon a stop.
• Demo follows the written rules. Demo deployments fill under the same execution rules as a backtest: a market order fills at the next bar's open, and when a stop and target are both reached in one bar the stop fills first unless finer data says otherwise.
• Live uses the side that can trade. A buy is triggered and filled on the ask and a sell on the bid. A long trade's stop and target trigger on the bid, a short trade's on the ask (E3, E4, E5). Backtests have no spread, so this is one reason live results differ.
• Guards still apply. max_daily_loss stops new entries until the next UTC day, and max_drawdown pauses the deployment until you resume it (E20).
• The deployment chooses where it runs. A script says what it was written for, and that comes filled in, but the market, the bar size, the trade size and the balance to trade belong to the deployment. A strategy written for EURUSD on the hour can be deployed on gold on five-minute bars by changing two fields.
• Demo or live is said plainly. Demo fills against the AlgoBars engine and costs nothing. Live sends real orders to a real broker.
• Live sizes the way the test did. The live runner places a stop where the backtest placed it and sizes a trade the same way, so what was tested is what trades.
• Edits are explained first. Changing a script that is already running shows what the change would do once it is live, before you make it.

Chart replay uses the same runner and the same rules, so what appears in replay is what the script would have done.

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Generated strategies are not written by a model. Entries, filters, exits and management are assembled from pieces of the language that are known to compile, and every candidate is then compiled and backtested. A strategy is only handed back once it has actually traded, so you never receive something that looks plausible and does nothing. The same seed and the same bars give the same strategy every time.

What comes back is ordinary AlgoBarsX. Read its plain-English description, open it in the Terminal and change it.

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• It was created on the last bar. A market order fills at the next bar's open. With no next bar it is reported as unfilled (E1).
• Price never reached it. A buy limit fills when the low is at or below its price, a buy stop when the high is at or above it. Sells mirror that (E4).
• It expired. expires: 10 bars cancels at the close of the tenth bar after it was placed (E17).
• A limit rejected it. max_open, max_open_per_side, pyramiding, max_total_risk and min_distance are checked when the entry would fill. A rejected entry is recorded with its reason (E19).
• It was outside trading hours. With trade_only, entries are only created inside the listed sessions (E22).
• A loss guard had tripped. After max_daily_loss, new entries are rejected until the next UTC day (E20).
• There was already a trade the other way. The default for opposite is ignore (E18).

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• Backtests have no costs. No spread, commission, fees, swaps or slippage. Profit is the price difference (E12).
• Live trades on the bid and the ask. A buy fills on the ask, a sell on the bid, and stops and targets trigger on the side that can actually trade (E3, E5). A backtest has one price.
• Gaps move fills. When a bar opens beyond a stop, the fill is the open, not the stop price (E8).
• The broker decides live fills. A live trade exists only once your broker confirms it. Execution speed and liquidity are outside the script.
• The data may be thinner. data.coverage tells a script how much history it has and whether it is exact.

Past performance does not guarantee future results.

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When a bar reaches both the stop and the target, the engine walks the 1-minute bars inside it to see which came first (E6). If finer data cannot tell, the stop fills (E7). The engine never picks the flattering answer, so a backtest errs on the side of caution.

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• A stop written as a distance (25 pips, atr(14) * 2, 2R) is measured from the actual fill price. If the entry fills 8 pips higher after a gap, the stop is 8 pips higher too (E9).
• A stop written as a level (low[1], 1.0850) stays exactly where you put it. If a gap makes it invalid, for example a long stop at or above the fill, the order is cancelled and recorded as “stop beyond entry” (E10).
• breakeven and trail move stops during the trade, and a trailing stop only ever tightens (E13, E14).

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Risk-based size is rounded down to the market's lot step, so it is usually a little under your risk. If it falls below the minimum lot, the trade opens at the minimum lot and is marked “above requested risk”, with the risk it actually carries (E11). Use size_for to see the size before you trade it.

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An account with nothing left cannot trade on. When equity is gone, the backtest stops at that bar, closes what was open and marks the run as liquidated, with the bar and the time. Everything after that point did not happen, so the engine does not pretend it did. The replay stops at the same place.

If this surprises you, check the trade size and the stop first. A large fixed lot size on a small starting balance is the usual cause.

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A script that says buy and nothing more is a reasonable script. It means “the usual amount”, and the usual amount belongs to wherever the script is run, not to the script. In the Terminal that is the Lot size in the backtest panel and the Trade size when you deploy. When nothing is set anywhere, it is the smallest lot the market deals in.

A script that names a size: or a risk: is never overruled.

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An order that names a market the run is not trading is refused, with a reason. Filling it on the current market would be worse than not filling it: a pairs trade would quietly become two orders on one instrument. List every market the strategy trades under markets: in the header. The live runner refuses it too, and says so.

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An average of 200 bars has nothing to say for the first 199. Each function's reference entry gives its warm-up, and rules do not run until the script's warm-up has passed. The compiler works the warm-up out for you. Set warmup: in the header to override it.

A higher bar size also shows nothing new until its candle closes, by design. A 5-minute rule never sees a 4-hour bar early.

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An alert's own settings decide when it may speak again. The default repeat is once per bar. cooldown sets the shortest gap between messages, and expires switches the alert off. Testing an alert lists the messages it sent and the ones it held back, with the reason.

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A script with evaluate: tick needs the price path inside each bar. When a bar has no 1-minute data stored, its own open, high, low and close are used instead, the run is labelled “approximate intrabar”, and the affected bars are listed (E2). Treat those stretches with more caution.

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Every message names the problem, the line and the column, and says what to do. Many carry a one-click fix. Search this page for the code, such as AS0304, or browse Compiler Messages. The most common ones:

• AS0201 a name the compiler does not know, usually a typo. It suggests the nearest name.
• AS0302 a number with no unit where a distance is expected.
• AS0303 and AS0304 an R target or a risk-based size with no stop to measure from.
• AS0003 a tab used for indentation. Use spaces.
• AS0401 something in the wrong kind of script, such as an order in an indicator.

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• pane: price draws over the price chart. pane: new gives the indicator its own pane.
• plot draws a series. as gives the plot a name. Colours can depend on a condition.
• export publishes a value. Anything exported can be read by a strategy, an alert or another indicator that uses this one.

Using an indicator or a library from another script

You import by name and version, give it a short name with as, and set its inputs in brackets. After that, ribbon.up reads like any other value. A script names the version it uses, so an update to the indicator does not silently change a strategy that depends on it.

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There are 26 drawing commands. Each is documented under Drawing commands.

• Give a drawing an id: to update the same object on later bars instead of adding a new one.
• Positions are written as (bar, price) pairs, such as (bar.index - 20, lowest(low, 20)).
• Colours: ten named colours, hex values, .fade(percent), and gradient, linear_gradient and radial_gradient.

The canvas

When no command fits, on render(canvas) gives you a vector canvas for the visible range: paths, lines, fills and text.

Examples: Volatility Regime Canvas, Volume Heatmap, Multi-Timeframe Trend Table, Opening Range Dashboard.

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notify sends the message. In version 1 it is delivered in the app and in AI chat. Testing an alert shows you the messages it would have sent and the ones its own settings held back.

Alerts that watch the account, not the chart

More: Daily risk guard, Intrabar spike, Tokyo open gap, Distribution shift.

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A library holds functions, constants and types. It cannot place orders or draw (AS0405). Import it with use library "Quant Toolkit" v2 as qt and call qt.kelly_fraction(0.55, 1.8).

Examples: Quant Toolkit, Risk Parity, Ranking Tools, and a strategy that uses one: Kelly Sized Breakout.

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sma ema wma rma smma hma vwma dema tema kama alma t3 zlema

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rsi stoch stoch_rsi macd cci williams_r roc momentum tsi ultimate_osc awesome_osc ppo cmo trix mfi