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docs/en/reference/CONDITION.md

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+# CONDITION
+
+An object that describes a comparison of two operands. Configured by three fields in the script and invoked through [`CHECK`](#check) or one of the control-flow methods ([`BREAK`](#break), [`ONE_BREAK`](#one_break)).
+
+## Fields
+
+### OPERAND1
+
+```
+STRING OPERAND1
+```
+
+The left-hand operand of the comparison. The field holds the operand's textual form, which is parsed on every evaluation. Accepted forms:
+
+- a quoted string literal (`"..."` or `'...'`),
+- a boolean literal (`TRUE`, `FALSE`),
+- a numeric literal (`5`, `-3.14`),
+- a variable name (its value is fetched; for variables of type [`EXPRESSION`](index.md), `CONDITION`, or [`COMPLEXCONDITION`](COMPLEXCONDITION.md), the variable is recursively evaluated),
+- a script fragment — text starting with `[`, `*`, or containing the `^` or `|` operators.
+
+### OPERAND2
+
+```
+STRING OPERAND2
+```
+
+The right-hand operand of the comparison. The interpretation rules are identical to those of `OPERAND1`.
+
+### OPERATOR
+
+```
+STRING OPERATOR
+```
+
+The comparison operator. Defaults to `EQUAL`. Accepted values:
+
+| Value | Meaning |
+|---|---|
+| `EQUAL` | equal to |
+| `NOTEQUAL` | not equal to |
+| `LESS` | less than |
+| `GREATER` | greater than |
+| `LESSEQUAL` | less than or equal |
+| `GREATEREQUAL` | greater than or equal |
+
+## Methods
+
+### BREAK
+
+```
+void BREAK([BOOL emitSignals])
+```
+
+Evaluates the condition. If the result is `TRUE`, aborts the entire current call tree (the same effect as [`@BREAK`](../engine/scripts.md#jump-operators)). If the result is `FALSE`, the method has no effect.
+
+**Parameters**
+
+- `emitSignals` — (optional) if `TRUE`, also fires [`ONRUNTIMESUCCESS`](#onruntimesuccess) or [`ONRUNTIMEFAILED`](#onruntimefailed) depending on the result. Defaults to `FALSE`.
+
+**Examples**
+
+```
+COND1^BREAK(TRUE);
+CONDKONTROLA^BREAK(TRUE);
+```
+
+### CHECK
+
+```
+BOOL CHECK([BOOL emitSignals])
+```
+
+Evaluates the condition and returns the comparison result.
+
+**Parameters**
+
+- `emitSignals` — (optional) if `TRUE`, also fires [`ONRUNTIMESUCCESS`](#onruntimesuccess) or [`ONRUNTIMEFAILED`](#onruntimefailed) depending on the result. Defaults to `FALSE`.
+
+**Returns**: [`BOOL`](BOOL.md) — the comparison result.
+
+**Examples**
+
+```
+CONPR1^CHECK(TRUE);
+CONPR2^CHECK(TRUE);
+```
+
+### ONE_BREAK
+
+```
+void ONE_BREAK([BOOL emitSignals])
+```
+
+Evaluates the condition. If the result is `TRUE`, aborts only the current procedure (the same effect as [`@ONEBREAK`](../engine/scripts.md#jump-operators)). If the result is `FALSE`, the method has no effect.
+
+**Parameters**
+
+- `emitSignals` — (optional) same as for [`BREAK`](#break).
+
+**Examples**
+
+```
+COND1^ONE_BREAK(TRUE);
+CONDREMOVEMENUITEM^ONE_BREAK(TRUE);
+```
+
+## Signals
+
+### ONRUNTIMESUCCESS
+
+Fired when the condition evaluated to `TRUE` and `emitSignals` was `TRUE`.
+
+### ONRUNTIMEFAILED
+
+Fired when the condition evaluated to `FALSE` and `emitSignals` was `TRUE`.